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A2 adverb #2,000 پرکاربردترین 8 دقیقه مطالعه

कब से

kab se رتبه 2,000

At the A1 level, 'कब से' (Kab se) is introduced as a basic question phrase to ask about time. Learners should focus on its literal meaning: 'Since when?'. It is used in very simple sentences to ask about ongoing states, such as 'You are here since when?' (तुम कब से यहाँ हो?). At this stage, the goal is to recognize the phrase and understand that 'से' (se) adds the meaning of 'since' or 'from' to the question word 'कब' (when). Learners should practice it with simple verbs like 'होना' (to be) and 'रहना' (to live/stay). It's a vital tool for basic social interaction, allowing a beginner to ask how long someone has been in a place or how long they have been doing a simple activity. The focus is on the present tense and immediate context.

At the A2 level, learners begin to use 'कब से' with the present continuous tense (रहा है / रही है). This is the most common and natural way to use the phrase. You will learn to ask questions like 'Since when have you been learning Hindi?' (आप कब से हिंदी सीख रहे हैं?). The A2 learner understands that 'कब से' covers both 'since when' (a point in time) and 'for how long' (a duration) in English. You should also be able to answer these questions using 'से', such as 'दो साल से' (for two years). This level involves expanding the vocabulary used with 'कब से' to include daily routines, work, and hobbies. It's about moving from simple states to active, ongoing processes.

At the B1 level, the use of 'कब से' becomes more fluid and is integrated into more complex sentence structures. Learners can use it in the past continuous tense to ask about actions that were ongoing at a certain point in the past ('Since when had you been waiting?'). You also start to use 'कब से' in slightly more abstract contexts, such as asking about the duration of feelings or opinions. At this stage, you should be comfortable distinguishing 'कब से' from 'कब तक' (until when) and 'कितनी देर से' (for how long) in various conversational scenarios. You might also encounter 'कब से' in subordinate clauses or as part of more detailed inquiries in professional or academic settings.

At the B2 level, 'कब से' is used with a higher degree of nuance, including rhetorical uses and expressions of sarcasm or surprise. For example, 'Since when did you become such an expert?' (तुम कब से इतने बड़े एक्सपर्ट बन गए?). The learner understands the subtle shift in tone that 'कब से' can convey depending on the context and intonation. You can also use it in complex conditional sentences or when discussing long-term trends and historical durations. B2 learners should be able to handle 'कब से' in formal debates, news reports, and literary texts, recognizing how it anchors a discussion in a temporal starting point. The focus here is on the versatility of the phrase across different registers of speech.

At the C1 level, 'कब से' is used with absolute precision in sophisticated discourse. The learner can navigate the philosophical and temporal implications of the phrase in literature and high-level journalism. You might use it to question the origins of social movements, legal precedents, or scientific theories. At this level, the distinction between 'कब से' and its synonyms is handled with stylistic flair. You understand how 'कब से' functions within the broader system of Hindi postpositions and how it interacts with different verb aspects to create specific temporal meanings. The C1 learner can also use 'कब से' in creative writing to evoke a sense of longing or historical depth, manipulating the phrase to suit the specific emotional or intellectual needs of the text.

At the C2 level, mastery of 'कब से' is complete and instinctive. The learner can use the phrase in any context, from the most colloquial slang to the most formal academic prose. You are aware of the historical evolution of the phrase and its usage in various Hindi dialects. At this level, you can use 'कब से' to engage in deep linguistic analysis or to produce complex literary works where time and duration are central themes. You can play with the phrase, using it in wordplay, puns, or highly stylized rhetorical devices. For a C2 speaker, 'कब से' is not just a vocabulary item but a flexible tool for precise temporal expression, used with a native-like grasp of its every possible connotation and nuance.

تمرین کن مثال‌ها نکات و راهنمایی‌ها

कब से در ۳۰ ثانیه

Means 'Since when' or 'For how long'.
Used for ongoing actions starting in the past.
Combines 'Kab' (When) and 'Se' (Since).
Commonly used with continuous verb tenses.

The Hindi phrase कब से (Kab se) is a fundamental interrogative adverbial phrase used to inquire about the starting point of an action or the duration of a state that continues into the present. In English, it most accurately translates to 'Since when?' or 'For how long?'. Structurally, it combines the interrogative pronoun 'कब' (kab - when) with the postposition 'से' (se - from/since/with). This combination is essential for navigating temporal contexts in Hindi, particularly when dealing with the perfect continuous aspect. Understanding 'कब से' requires a grasp of how Hindi treats time as a linear progression from a specific point. Unlike English, which often distinguishes between 'since' (point in time) and 'for' (duration), Hindi frequently uses 'से' for both, making 'कब से' the universal query for the origin of an ongoing event.

Grammatical Category: Interrogative Adverbial Phrase
Literal Translation: 'When from' or 'From when'

आप यहाँ कब से काम कर रहे हैं? (Since when have you been working here?)

In a deeper linguistic sense, 'कब से' serves as a bridge between the past and the present. It forces the respondent to identify a temporal anchor. Whether the answer is 'two hours' (duration) or 'Monday' (point in time), the question remains the same. This simplifies the learner's task compared to English, where one must choose between 'How long' and 'Since when'. In Hindi, the context of the verb (usually in the continuous form) provides the necessary framework. For example, 'तुम कब से सो रहे हो?' (Since when have you been sleeping?) implies the person is still asleep or has just woken up. The phrase is ubiquitous in daily conversations, from casual inquiries about a friend's arrival to formal investigations into project timelines. It is the key to unlocking the history of a current situation.

वह कब से बीमार है? (Since when has he been ill?)

Core Usage: Inquiring about the inception of a state or action.

Using कब से correctly involves placing it before the verb, typically following the subject. The most common sentence structure is: [Subject] + [कब से] + [Verb/Action]. Because it asks about duration or a starting point, it is almost always paired with the auxiliary verbs 'रहा है/रही है/रहे हैं' (present continuous) or 'था/थी/थे' (past continuous) to indicate an ongoing process. For instance, 'तुम कब से इंतज़ार कर रहे हो?' (Since when have you been waiting?). Here, the focus is on the stretch of time from the moment the waiting began until now. It is important to note that 'कब से' can also be used with stative verbs or adjectives to ask about the duration of a condition, such as 'तुम कब से यहाँ हो?' (Since when are you here?).

बारिश कब से हो रही है? (Since when has it been raining?)

Syntactic Position: Usually placed after the subject and before the main verb.

Advanced usage of 'कब से' can involve rhetorical questions or expressions of surprise. If someone suddenly starts acting differently, one might ask, 'तुम कब से इतने समझदार हो गए?' (Since when did you become so wise?). In this context, the phrase highlights a perceived change in behavior. Furthermore, 'कब से' is often contrasted with 'कब तक' (until when). While 'कब से' looks backward to the origin, 'कब तक' looks forward to the conclusion. Mastering 'कब से' also requires understanding the response format. A response to 'कब से' will usually involve a time marker followed by 'से', such as 'दो घंटे से' (for two hours) or 'कल से' (since yesterday). This symmetry between question and answer makes it a very logical component of Hindi grammar.

आप कब से हिंदी सीख रहे हैं? (Since when have you been learning Hindi?)

You will encounter कब से in a wide variety of social and professional settings. In a medical context, a doctor will invariably ask, 'आपको कब से बुखार है?' (Since when have you had a fever?) to establish the onset of symptoms. In a corporate environment, a manager might ask, 'यह प्रोजेक्ट कब से चल रहा है?' (Since when has this project been ongoing?) to track progress. In the domestic sphere, parents often ask children, 'तुम कब से टीवी देख रहे हो?' (Since when/How long have you been watching TV?) as a way of monitoring their activities. The phrase is also a staple of Hindi cinema (Bollywood) and literature, often used in emotional dialogues to emphasize long-standing feelings or grievances, such as 'मैं कब से तुम्हारा इंतज़ार कर रहा हूँ' (I have been waiting for you for so long/since whenever).

ये नल कब से टपक रहा है? (Since when has this tap been leaking?)

Common Settings: Hospitals, Offices, Schools, Homes, Public Transport.

In news reporting, 'कब से' is used to provide historical context to current events, such as 'यह कानून कब से लागू है?' (Since when has this law been in effect?). In casual street conversations, you might hear it when someone is frustrated by a delay: 'बस कब से नहीं आई?' (Since when has the bus not come?). The versatility of the phrase lies in its ability to handle both precise chronological inquiries and vague, emotive expressions of duration. It is one of those 'high-frequency' phrases that, once learned, seems to pop up in almost every conversation involving time. Listening for 'कब से' in podcasts or movies is an excellent way to understand the natural rhythm and intonation with which native speakers use it to express everything from curiosity to annoyance.

आप इस शहर में कब से रह रहे हैं? (Since when have you been living in this city?)

One of the most frequent errors for English speakers is confusing कब से with 'कितनी देर से' (kitni der se). While 'कब से' asks for the starting point ('Since when'), 'कितनी देर से' specifically asks for the duration ('For how long/How much time'). Although in many contexts they are interchangeable in Hindi, 'कब से' is more versatile. Another common mistake is forgetting the 'से' (se). Saying just 'कब' (kab) asks 'When' (a specific point in time for a completed or future action), whereas 'कब से' implies a continuous duration. For example, 'तुम कब आए?' (When did you come?) vs. 'तुम कब से यहाँ हो?' (Since when are you here?). The former is about a finished event, the latter about an ongoing state.

Incorrect: तुम कब इंतज़ार कर रहे हो?
Correct: तुम कब से इंतज़ार कर रहे हो?

Confusion Point: Confusing 'कब' (When) with 'कब से' (Since when).

Learners also sometimes struggle with the verb tense. Because 'कब से' implies an action that started in the past and continues now, it must be used with a continuous tense. Using a simple present tense like 'तुम कब से यहाँ रहते हो?' is technically acceptable in some dialects but 'तुम कब से यहाँ रह रहे हो?' is grammatically more robust for an ongoing stay. Additionally, avoid using 'कब से' for future actions; for that, you would use 'कब शुरू होगा' (When will it start?). Finally, be careful with the placement of 'से'. It must always follow 'कब'. Reversing them or separating them will make the sentence unintelligible. Consistent practice with the 'Subject + कब से + Verb' formula will help eliminate these common pitfalls.

Avoid: से कब (Se kab) - Always use कब से (Kab se).

To truly master कब से, it is helpful to compare it with other temporal interrogatives. The most obvious comparison is with कब (Kab), which simply means 'When' and is used for a single point in time. Then there is कब तक (Kab tak), which means 'Until when' or 'By when', focusing on the end point or deadline. Another related phrase is कितनी देर से (Kitni der se), which translates to 'For how long' and is used when the speaker is interested in the specific quantity of time (minutes, hours, years) rather than the starting date or time. While 'कब से' can be answered with 'Monday', 'कितनी देर से' is usually answered with 'Two hours'.

कब (Kab): When (Point in time, e.g., 'When did you arrive?')
कब तक (Kab tak): Until when (End point, e.g., 'Until when will you stay?')
कितनी देर से (Kitni der se): For how long (Duration, e.g., 'How long have you been waiting?')

There is also जब से (Jab se), which is the relative counterpart meaning 'Since' (as in 'Since I moved here...'). While 'कब से' asks the question, 'जब से' provides the condition or starting point in a statement. For example, 'जब से मैं यहाँ आया हूँ, खुश हूँ' (Since I came here, I am happy). Understanding the relationship between 'कब' (interrogative) and 'जब' (relative) is a key feature of Hindi grammar. Finally, कहाँ से (Kahan se) means 'From where', which is a spatial rather than temporal inquiry. Keeping these distinctions clear will prevent confusion and allow for more precise communication in Hindi.

Comparison: कब से (Since when) vs. कब तक (Until when).

چقدر رسمی است؟

رسمی

غیر رسمی

عامیانه

سطح دشواری

گرامر لازم

مثال‌ها بر اساس سطح

तुम कब से यहाँ हो?

Since when are you here?

Simple present state with 'हो' (are).

वह कब से बीमार है?

Since when is he ill?

Stative use of 'कब से'.

आप कब से भूखे हैं?

Since when are you hungry?

Adjective 'भूखे' (hungry) used with 'कब से'.

यह कब से है?

Since when is this (here)?

Demonstrative 'यह' used as subject.

तुम कब से घर पर हो?

Since when are you at home?

Locative 'घर पर' used with 'कब से'.

वे कब से साथ हैं?

Since when are they together?

Plural subject 'वे' with 'हैं'.

माँ कब से रसोई में है?

Since when is mother in the kitchen?

Feminine singular subject 'माँ'.

तुम कब से तैयार हो?

Since when are you ready?

Adjective 'तैयार' (ready).

आप कब से हिंदी सीख रहे हैं?

Since when have you been learning Hindi?

Present continuous tense (masculine plural/respectful).

बारिश कब से हो रही है?

Since when has it been raining?

Present continuous tense (feminine singular).

तुम कब से मेरा इंतज़ार कर रहे हो?

Since when have you been waiting for me?

Compound verb 'इंतज़ार करना' in continuous form.

वह कब से सो रही है?

Since when has she been sleeping?

Present continuous tense (feminine singular).

बच्चे कब से खेल रहे हैं?

Since when have the children been playing?

Present continuous tense (masculine plural).

आप इस कंपनी में कब से काम कर रहे हैं?

Since when have you been working in this company?

Present continuous with locative phrase.

तुम कब से गाड़ी चला रहे हो?

Since when have you been driving the car?

Present continuous tense.

पक्षी कब से चहचहा रहे हैं?

Since when have the birds been chirping?

Onomatopoeic verb 'चहचहाना' in continuous form.

वह कब से इस समस्या के बारे में सोच रहा था?

Since when had he been thinking about this problem?

Past continuous tense (masculine singular).

तुम कब से जानते थे कि वह झूठ बोल रहा है?

Since when did you know that he was lying?

Past tense of 'जानना' (to know) used with 'कब से'.

सरकार कब से इस योजना पर विचार कर रही है?

Since when has the government been considering this plan?

Formal subject 'सरकार' with continuous verb.

तुम कब से गिटार बजाना सीख रहे हो?

Since when have you been learning to play the guitar?

Infinitive 'बजाना' used as an object of 'सीखना'.

वे कब से एक-दूसरे को जानते हैं?

Since when have they known each other?

Reciprocal pronoun 'एक-दूसरे' (each other).

तुम कब से यहाँ अकेले रह रहे हो?

Since when have you been living here alone?

Adverb 'अकेले' (alone).

यह दुकान कब से बंद है?

Since when has this shop been closed?

Adjective 'बंद' (closed) in a stative sentence.

आप कब से इस प्रोजेक्ट के लीडर हैं?

Since when have you been the leader of this project?

Noun 'लीडर' used as a complement.

तुम कब से इतने बड़े राजनीतिज्ञ बन गए?

Since when did you become such a big politician? (Sarcastic)

Rhetorical use expressing surprise or sarcasm.

यह परंपरा कब से चली आ रही है?

Since when has this tradition been going on?

Compound verb 'चली आना' indicating continuity over generations.

वैज्ञानिक कब से इस वायरस पर शोध कर रहे हैं?

Since when have scientists been researching this virus?

Formal vocabulary 'शोध' (research).

तुम्हें कब से लगने लगा कि मैं गलत हूँ?

Since when did you start feeling that I am wrong?

Inceptive verb 'लगने लगना' (to start feeling).

यह विवाद कब से सुलझने का नाम नहीं ले रहा?

Since when has this dispute shown no sign of being resolved?

Idiomatic expression 'नाम नहीं लेना' (to show no sign of).

आप कब से इस विचारधारा का समर्थन कर रहे हैं?

Since when have you been supporting this ideology?

Abstract noun 'विचारधारा' (ideology).

वह कब से अपनी गलतियों को छुपाने की कोशिश कर रहा है?

Since when has he been trying to hide his mistakes?

Complex verb structure with 'कोशिश करना'.

तुम कब से इतने लापरवाह हो गए हो?

Since when have you become so careless?

Adjective 'लापरवाह' (careless) with 'हो गए हो'.

मानव सभ्यता कब से प्रकृति के साथ खिलवाड़ कर रही है?

Since when has human civilization been toying with nature?

High-level vocabulary 'खिलवाड़ करना' (to toy with).

यह दार्शनिक प्रश्न कब से विचारकों को परेशान कर रहा है?

Since when has this philosophical question been troubling thinkers?

Abstract subject 'दार्शनिक प्रश्न' (philosophical question).

न्यायालय कब से इस मामले की निष्पक्षता पर संदेह कर रहा है?

Since when has the court been doubting the impartiality of this case?

Legal terminology 'निष्पक्षता' (impartiality).

साहित्य में कब से यथार्थवाद का प्रभाव दिखने लगा था?

Since when had the influence of realism started appearing in literature?

Literary term 'यथार्थवाद' (realism).

अर्थव्यवस्था कब से इस मंदी के दौर से गुज़र रही है?

Since when has the economy been going through this period of recession?

Economic term 'मंदी' (recession).

तुम कब से अपनी अंतरात्मा की आवाज़ को अनसुना कर रहे हो?

Since when have you been ignoring the voice of your conscience?

Metaphorical language 'अंतरात्मा की आवाज़' (voice of conscience).

यह कानून कब से अपनी प्रासंगिकता खोने लगा है?

Since when has this law started losing its relevance?

Formal term 'प्रासंगिकता' (relevance).

वह कब से इस गूढ़ रहस्य को सुलझाने का प्रयास कर रहा है?

Since when has he been attempting to solve this profound mystery?

Sophisticated adjective 'गूढ़' (profound/mysterious).

ब्रह्मांड की उत्पत्ति के पश्चात, समय का अस्तित्व कब से माना जाता है?

Since when is the existence of time considered to have begun after the origin of the universe?

Scientific/Philosophical inquiry with passive construction.

भाषा विज्ञान में कब से संरचनावाद को चुनौती दी जाने लगी थी?

Since when had structuralism begun to be challenged in linguistics?

Academic discourse on 'संरचनावाद' (structuralism).

वैश्विक राजनीति में कब से शक्ति संतुलन का यह नया स्वरूप उभरा है?

Since when has this new form of balance of power emerged in global politics?

Political science term 'शक्ति संतुलन' (balance of power).

मनोविश्लेषण के क्षेत्र में कब से अवचेतन की अवधारणा को प्रधानता मिली?

Since when did the concept of the subconscious gain prominence in the field of psychoanalysis?

Psychological term 'अवचेतन' (subconscious).

कला के इतिहास में कब से अमूर्तता ने यथार्थ को प्रतिस्थापित करना प्रारंभ किया?

Since when in the history of art did abstraction begin to replace reality?

Art history terminology 'अमूर्तता' (abstraction).

संवैधानिक नैतिकता की यह व्याख्या कब से न्यायशास्त्र का अंग बनी?

Since when did this interpretation of constitutional morality become a part of jurisprudence?

Legal/Philosophical term 'न्यायशास्त्र' (jurisprudence).

पारिस्थितिक तंत्र में कब से यह असंतुलन दृष्टिगोचर होने लगा है?

Since when has this imbalance become visible in the ecosystem?

Environmental science term 'दृष्टिगोचर' (visible/apparent).

आध्यात्मिक चेतना के विकास में कब से मौन को इतनी महत्ता दी गई है?

Since when has silence been given such importance in the development of spiritual consciousness?

Spiritual/Philosophical inquiry.

ترکیب‌های رایج

कब से इंतज़ार

कब से बीमार

कब से यहाँ

कब से काम

कब से शुरू

कब से जानते

कब से रह

कब से चल

कब से हो

कब से देख

عبارات رایج

तुम कब से यहाँ हो?

यह कब से चल रहा है?

आप कब से जानते हैं?

बारिश कब से हो रही है?

वह कब से सो रहा है?

कब से कब तक?

तुम कब से इतने समझदार हो गए?

मैं कब से कह रहा हूँ!

यह दुकान कब से बंद है?

तुम कब से गाड़ी चला रहे हो?

اغلب اشتباه گرفته می‌شود با

कब से vs कब

Means 'When' (point in time), not 'Since when' (duration).

कब से vs कितनी देर से

Specifically asks for the amount of time (minutes/hours).

कब से vs कहाँ से

Means 'From where' (spatial), not 'From when' (temporal).

اصطلاحات و عبارات

"कब से कब तक"

From when to when (asking for a specific range).

"कब से ही"

Since a long time ago (emphatic).

"न जाने कब से"

God knows since when (expressing a very long time).

"जाने कब से"

Since who knows when.

"कब से आँखें बिछाए"

Waiting eagerly for a very long time.

"कब से रट लगा रखी है"

Repeating the same thing for a long time.

"कब से इंतज़ार में पलकें बिछाना"

To wait very anxiously for a long time.

"कब से बात चल रही है"

The discussion has been going on for a long time.

"कब से जी रहे हैं"

Living (in a certain way) for a long time.

"कब से प्यासा"

Thirsty for a long time (often metaphorical).

به‌راحتی اشتباه گرفته می‌شود

कब से vs जब से

कब से vs कब तक

कब से vs अभी से

कब से vs तब से

कब से vs कभी से

الگوهای جمله‌سازی

[Subject] कब से [Verb-ing] है?

तुम कब से रो रहे हो?

[Subject] कब से [Adjective] है?

वह कब से बीमार है?

[Subject] कब से [Noun] है?

आप कब से डॉक्टर हैं?

[Object] कब से [Verb-ing] है?

बारिश कब से हो रही है?

[Subject] कब से [Locative] है?

वे कब से घर पर हैं?

[Subject] कब से [Verb-Past]?

तुम कब से जानते थे?

[Subject] कब से [Verb-Future]?

यह कब से शुरू होगा? (Rare, usually 'कब')

कब से कब तक?

ऑफिस कब से कब तक खुला है?

نحوه استفاده

emotional tone

Can be used to express frustration if someone is late.

duration vs point

In Hindi, 'कब से' handles both 'since' and 'for' questions.

اشتباهات رایج

نکات

Verb Matching

Make sure your verb matches the subject. 'तुम कब से खेल रहे हो?' (Masculine) vs 'तुम कब से खेल रही हो?' (Feminine).

Natural Flow

Native speakers often say 'कब से' very quickly. Practice it as a single word 'Kabse'.

Pairing

Always pair 'कब से' with 'रहा है/रही है' for ongoing actions.

Context Clues

If you hear 'से' at the end of a question word, it's likely asking about duration or origin.

Punctuation

Don't forget the question mark (?) at the end of sentences starting with 'कब से'.

Politeness

Use 'आप' instead of 'तुम' when asking 'कब से' to elders or strangers.

The 'S' Rule

Remember 'Se' = 'Since'. Both start with S.

Stative Verbs

You can use 'कब से' with 'जानना' (to know) even though it's not usually continuous: 'तुम उसे कब से जानते हो?'

Kab vs Kab Se

Kab = Point. Kab Se = Line (Duration).

Daily Life

Try asking yourself 'कब से' questions about your daily habits to practice.

حفظ کنید

ریشه کلمه

Sanskrit 'कदा' (kadā) meaning 'when' + Old Hindi postposition 'से' (se) derived from Sanskrit 'सकाश' (sakāśa) or 'सम' (sama).

بافت فرهنگی

Using 'आप' (formal you) with 'कब से' is standard for showing respect.

Asking about duration is a common small-talk topic in India.

تمرین در زندگی واقعی

موقعیت‌های واقعی

شروع‌کننده‌های مکالمه

"आप कब से हिंदी सीख रहे हैं?"

"आप इस शहर में कब से रह रहे हैं?"

"आप अपनी वर्तमान नौकरी कब से कर रहे हैं?"

"आप कब से यहाँ इंतज़ार कर रहे हैं?"

"यह फिल्म कब से चल रही है?"

موضوعات نگارش

लिखिए कि आप कब से अपनी पसंदीदा हॉबी कर रहे हैं।

आप कब से अपने सबसे अच्छे दोस्त को जानते हैं?

आप कब से एक नई भाषा सीखने का सोच रहे थे?

आपके शहर में सबसे पुरानी इमारत कब से है?

आप कब से इस डायरी को लिख रहे हैं?

سوالات متداول

10 سوال

Yes, in Hindi 'कब से' is commonly used to ask both 'Since when' and 'For how long' for ongoing actions.

No, 'कब से' is used for actions that have already started. For future starting times, use 'कब शुरू होगा' or 'कब से शुरू होगा'.

'कब' asks for a specific time (e.g., 'When did you eat?'), while 'कब से' asks for a starting point of an ongoing state (e.g., 'Since when have you been eating?').

Answer with a time + 'से'. For example, 'दो बजे से' (Since 2 o'clock) or 'दो घंटे से' (For two hours).

It is neutral and can be used in both formal and informal contexts.

No, the postposition 'से' must always follow the word it modifies. So it is always 'कब से'.

Neither is 'better'; 'कितनी देर से' is more specific about duration, while 'कब से' is more general about the starting point.

Usually, yes, if the action is ongoing. If it's a state (like being ill), a simple 'है' (is) is enough.

Yes, like 'Since when did you become so smart?' (तुम कब से इतने होशियार हो गए?).

It is typically introduced at the A2 level as learners begin to use continuous tenses.