I-love-you-to vs. Too: What's the Difference?

1. 1To as a Preposition: In this role, to establishes a relationship, often involving direction, time, or reception. It answers questions like Where?, To whom?, or Until when?.

• Direction & Destination: This is the most concrete use, signifying movement toward a place, person, or state. Think of it as drawing a vector from point A to point B. For example, in She is driving to the office, the word to connects the action of driving with its destination.
• Recipient or Beneficiary: To is used with verbs of giving, sending, or communicating to identify the receiver. In Please give the report to me, to clarifies who receives the report. This distinguishes the direct object (the report) from the indirect object (me).
• Relationship & Connection: To can also link abstract concepts. In the key to success, to connects the key with its purpose, success. It defines the relationship between two nouns.
• Time & Range: It is used in fixed expressions of time, such as telling time (It's ten to five, meaning 4:50) or defining a period (He works from Monday to Friday).

1. 1To as an Infinitive Marker: This is a critically important function where to does not act as a preposition. Instead, it pairs with the base form of a verb (e.g., speak, go, learn) to create an infinitive phrase (to speak, to go, to learn). The to-infinitive acts as a single grammatical unit that can function as a noun, an adjective, or an adverb.

• Expressing Purpose: The most common use of the infinitive is to explain why an action is done. In I am studying to pass the exam, the phrase to pass the exam explains the purpose of studying.
• As the Subject or Object of a Verb: An infinitive phrase can be the object of another verb, particularly verbs of wanting, planning, or needing. For instance, in She wants to leave, the phrase to leave is the object of the verb wants.

1. 1Too as an Adverb of Addition (meaning also or in addition): This is the most frequent use. It indicates that a statement is also true for another subject. It is almost always placed at the end of a clause. For example, John is coming to the party, and Sarah is coming, too.

1. 1Too as an Adverb of Degree (meaning excessively or more than is desirable): In this role, too modifies an adjective or an adverb to indicate that a quality has exceeded a necessary or appropriate limit. The music is too loud. This implies a negative consequence (e.g., it hurts my ears). You are driving too fast implies you are exceeding the speed limit or a safe speed.

• This function is often used in the powerful construction too + [adjective/adverb] + to + [infinitive]. This pattern links an excess with a resulting inability. For example, I am too tired to cook dinner means that the excess of tiredness prevents the action of cooking.

No. The phrase is a common written representation of a spoken mistake. When someone says I love you and the other person replies, they mean I love you, also. The correct word for also is too. The correct written response is I love you, too. Using to is grammatically incorrect as it has no function in that position.

It's possible but rare and very informal. For example: I want a new computer. Too, I need a new keyboard. In this case, it means In addition. However, it's much more standard and stylistically better to use Also,, Additionally,, or In addition, to start a sentence. Using Too, at the start can sound abrupt or even a bit archaic.

Me too is a highly common, informal response that functions as a complete conversational turn. I am, too (or I do, too, I can, too, etc.) is a full grammatical clause. It's slightly more formal and precise. Both are correct, but Me too is far more frequent in casual speech. You would be more likely to write I am, too in a semi-formal email.

Yes. The "extra O" trick. Think of the extra o in too as representing something extra or more. Too means also (something more is being added) or excessively (more than enough). If the meaning is not about adding more, you use to.