B1 · Intermediário Capítulo 13

Rules, Advice, and Instructions

4 Regras totais
48 exemplos
6 min
Regras neste capítulo Prática rápida

Chapter in 30 Seconds

Master the art of giving helpful advice and clear instructions with confidence.

  • Suggest better choices using the modal verb should.
  • Express non-negotiable rules and necessities using must.
  • Link specific conditions to advice and direct commands.
Command the room and guide others with precision.

O que você vai aprender

Feeling ready to give advice and strong instructions like a pro? This chapter will show you how to use if with commands and express what must be done, helping you guide others clearly and effectively in everyday conversations.

Learning Objectives

By the end of this chapter, you will be able to:

  1. 1
    By the end you will be able to offer polite recommendations for common problems using should.
  2. 2
    By the end you will be able to state firm legal or personal requirements using must.
  3. 3
    By the end you will be able to construct complex conditional sentences to give advice based on specific situations.

Guia do capítulo

Overview

As you continue your journey in B1 English grammar, you’re building the skills to connect with people and express yourself clearly in a wide range of situations. This chapter is all about giving effective English rules, advice, and instructions. Imagine being able to help a friend, offer clear guidance, or explain important steps without sounding aggressive or unclear.
That's exactly what you'll learn here!
We'll dive into the subtle art of using words like should to offer helpful recommendations, like
You should try that new cafe.
You'll also master must for those times when something is truly essential, as in
You must submit your report by Friday.
We’ll also explore how to combine these with the first conditional – using if clauses to give advice and commands that are relevant to specific situations, such as
If you want to pass the exam, you should study every day
or
If you see a problem, tell your manager immediately.
By the end, you'll be confidently guiding others and understanding important directions like a native speaker.

How This Grammar Works

Learning to give and understand rules, advice, and instructions effectively makes your English sound much more natural and confident. Let's explore how these pieces fit together, moving from gentle suggestions to strong directives.
First, for friendly advice and recommendations, we use should. This is your go-to for suggesting the best course of action without being too strong or bossy. For example,
You should drink more water
or
They should call their parents more often.
It implies a good idea, but the choice is still up to the listener.
When something is absolutely essential, a strong obligation, or a logical necessity, we use must. This isn't a suggestion; it's a rule, a requirement, or something that is highly certain. Think of signs like
All visitors must check in at reception
or personal vows like
I must finish this project tonight.
If there’s no other option, or the consequences of not doing it are serious, must is the word.
Now, let's add a condition! The first conditional for advice (should) combines a possible future situation with advice. The structure is simple: If + present simple, should + base verb.
This allows you to give advice that is specific and relevant to a particular scenario. For instance,
If you feel tired, you should take a break
or
If it rains tomorrow, we should bring umbrellas.
This makes your advice more practical and targeted.
Finally, we have the first conditional for commands & advice (If + Imperative). Here, instead of using should, you give a direct command or instruction in the second part of the sentence. The structure is: If + present simple, imperative (base verb form).
For example,
If you arrive late, wait outside
or
If you have any questions, ask the teacher.
This is perfect for giving clear, actionable instructions based on a potential future event. These structures together give you a powerful toolkit for guiding conversations and ensuring clarity in your interactions.

Common Mistakes

It's easy to mix up these useful phrases. Here are some common pitfalls and how to avoid them:
  1. 1✗ Wrong: You must try the new coffee shop. (Sounds too strong, like an order)
✓ Correct: You should try the new coffee shop. (A friendly recommendation)
*Explanation:* Use should for suggestions, not must, which implies a necessity or obligation.
  1. 1✗ Wrong: If you want to lose weight, you must to exercise. (Incorrect grammar with to)
✓ Correct: If you want to lose weight, you must exercise. (Correct verb form)
*Explanation:* After modal verbs like must or should, always use the base form of the verb without to.
  1. 1✗ Wrong: If it rains, you should to take an umbrella. (Incorrect grammar with to)
✓ Correct: If it rains, you should take an umbrella. (Correct verb form)
*Explanation:* Like with must, should is followed directly by the base verb form.

Real Conversations

Here’s how these grammar points appear in everyday chats:

A

A

"I'm really struggling with my English homework. It's so difficult!"
B

B

"Oh, really? If you're having trouble, you should ask the teacher for help during office hours. She's very approachable."
A

A

"My flight leaves at 6 AM tomorrow. I'm worried I'll miss it."
B

B

"Wow, that's early! You must set several alarms, and you should pack your bag tonight so you don't forget anything important."
A

A

"I'm going hiking this weekend, but the weather forecast looks a bit unpredictable."
B

B

If the weather changes suddenly, make sure you have a map and a fully charged phone. And if it starts raining heavily, turn back immediately!

Quick FAQ

Q

When should I use should versus must for advice?

Use should for advice, recommendations, or what's generally a good idea. It's a suggestion. Use must when there's a strong obligation, a rule, a necessity, or a strong personal conviction. It implies no real choice.

Q

Can I use if with must?

While grammatically possible (e.g.,

If you must leave, please close the door
), it's less common for *giving advice*. It usually expresses a resignation or necessity already acknowledged. For conditional advice, stick to should or an imperative.

Q

Is you should always polite?

Generally, yes, you should is polite. However, if used too frequently or with a lecturing tone, it can sometimes sound a little preachy. To soften it further, you can say

I think you should...
or
Perhaps you should...

Q

What's the difference between

If you want to...
and
If you need to...
when giving advice?

If you want to...
implies a personal desire or goal (e.g.,
If you want to improve, you should practice daily
).
If you need to...
implies a requirement or necessity (e.g.,
If you need to contact me, call this number
). Both are useful in conditional advice.

Cultural Context

In English, the way we give advice and instructions often reflects politeness and directness. While must clearly states an obligation, it can sometimes sound very direct, almost like an order, especially in informal contexts. Native speakers often prefer should or softer phrases (like
You might want to...
or I suggest you...) even for important advice, to maintain a friendly tone.
Using the first conditional with an imperative ("If you're cold, put on a jacket") is common and generally accepted as clear and direct, but still contextual. Understanding these nuances helps you sound more natural and avoid accidental rudeness.

Exemplos-chave (8)

1

You `should really try` the new coffee shop downtown; their lattes are amazing.

Você deveria mesmo experimentar a nova cafeteria no centro; os lattes deles são incríveis.

Dar conselhos e recomendações (Should)
2

I think we `should start` our project early to avoid any last-minute stress.

Acho que deveríamos começar nosso projeto cedo para evitar o estresse de última hora.

Dar conselhos e recomendações (Should)
3

You **must** hand in your assignment by Friday.

Você deve entregar sua tarefa até sexta-feira.

Must: Obrigação e Necessidade Fortes
4

I **must** remember to call my parents tonight.

Eu devo me lembrar de ligar para meus pais hoje à noite.

Must: Obrigação e Necessidade Fortes
5

`If you're hungry, you should grab a snack.`

Se você está com fome, você deveria pegar um lanche.

Primeiro Condicional para Conselhos (should)
6

`If it rains later, you should take an umbrella with you.`

Se chover mais tarde, você deveria levar um guarda-chuva.

Primeiro Condicional para Conselhos (should)
7

`If you feel cold, close the window.`

Se você sentir frio, feche a janela.

Primeiro Condicional: Comandos e Conselhos (If + Imperativo)
8

`If you're hungry, grab a snack from the fridge.`

Se você estiver com fome, pegue um lanche na geladeira.

Primeiro Condicional: Comandos e Conselhos (If + Imperativo)

Dicas e truques (4)

💡

Seja Suave

'Should' serve para sugestões leves, não para dar ordens. Ele convida à concordância, tornando seu conselho mais fácil de aceitar. Use 'must' para obrigações fortes. Por exemplo:
You should consider it.
frontend.learn_grammar.from_rule: Dar conselhos e recomendações (Should)
💡

Pense em 'Obrigação Forte'

Se você consegue substituir a frase por 'É absolutamente necessário que' ou 'É uma regra que você', então must é a escolha certa! Ele é bem mais forte que should:
You must wear a seatbelt.
frontend.learn_grammar.from_rule: Must: Obrigação e Necessidade Fortes
💡

Presente Simples no 'If'

Sempre use o tempo present simple na parte do 'if', mesmo que você esteja falando sobre algo no futuro. O sentido de futuro vem do 'should' na outra parte da frase.
If you come, you should tell me.
frontend.learn_grammar.from_rule: Primeiro Condicional para Conselhos (should)
💡

Mantenha a Direção com Imperativos

Lembre-se de usar a forma base do verbo para o seu comando ou conselho. Evite adicionar 'will' ou 'should' na oração principal, pois isso muda o significado para uma previsão ou sugestão, não uma instrução direta.
If you are tired, rest.
frontend.learn_grammar.from_rule: Primeiro Condicional: Comandos e Conselhos (If + Imperativo)

Vocabulário-chave (6)

recommend to suggest something as a good choice mandatory required by law or rules passenger a person traveling in a vehicle instruction detailed information on how to do something prohibit to formally forbid something advice guidance or recommendations

Real-World Preview

plane

At the Airport Security

stethoscope

A Visit to the Doctor

Review Summary

  • Subject + should + Verb (base form)
  • Subject + must + Verb (base form)
  • If + Present Simple, Subject + should + Verb (base)
  • If + Present Simple, [Imperative Verb]

Erros comuns

Modal verbs like 'should' and 'must' are followed directly by the base verb. Never use 'to' after them.

Wrong: You should to study more.
Correto: You should study more.

In conditional advice, the second clause still needs a subject (you, he, she) before the word 'should'.

Wrong: If you are hungry, should eat.
Correto: If you are hungry, you should eat.

In the 'if' clause of a first conditional, we use the Present Simple, not 'will'.

Wrong: If you will see him, tell him the news.
Correto: If you see him, tell him the news.

Next Steps

You've taken a huge step toward fluency! Being able to guide others is a key leadership skill in any language. Keep practicing these patterns and you'll be a master communicator in no time.

Write 5 rules for your favorite sport using 'must' and 'should'.

Look at a recipe and identify the conditional instructions.

Continue to: Fatos, Hábitos e Regras: O Mundo Como Ele É

Prática rápida (9)

Escolha o verbo imperativo correto para completar a frase.

`If you see a good movie playing, ___ me about it!`

✓ Correct! ✗ Not quite. Correct answer: tell
Depois da cláusula 'if', usamos a forma base do verbo para um comando direto.

frontend.learn_grammar.from_rule: Primeiro Condicional: Comandos e Conselhos (If + Imperativo)

Escolha a forma correta para completar o conselho.

You ___ remember to save your work frequently.

✓ Correct! ✗ Not quite. Correct answer: should
'Should' é usado aqui para dar um conselho ou uma recomendação, indicando que é uma boa ideia salvar o trabalho frequentemente.

frontend.learn_grammar.from_rule: Dar conselhos e recomendações (Should)

Qual frase dá um conselho corretamente?

Escolha a frase correta:

✓ Correct! ✗ Not quite. Correct answer: She should study harder for the test.
'Should' é seguido pela forma base do verbo ('study'), não 'studies'. 'Must to' está incorreto; 'must' não leva 'to'.

frontend.learn_grammar.from_rule: Dar conselhos e recomendações (Should)

Encontre e corrija o erro na frase.

Find and fix the mistake:

We must to study for the final exam.

✓ Correct! ✗ Not quite. Correct answer: We must study for the final exam.
Verbos modais como must são seguidos diretamente pela forma base do verbo principal. O 'to' está incorreto.

frontend.learn_grammar.from_rule: Must: Obrigação e Necessidade Fortes

Escolha a forma correta para completar o conselho.

If you have a headache, you ___ take some medicine.

✓ Correct! ✗ Not quite. Correct answer: should
Usamos should para dar conselhos. Will prevê um resultado, e can expressa habilidade.

frontend.learn_grammar.from_rule: Primeiro Condicional para Conselhos (should)

Encontre e corrija o erro na frase.

Find and fix the mistake:

They should to call before visiting.

✓ Correct! ✗ Not quite. Correct answer: They should call before visiting.
Depois do verbo modal 'should', o verbo principal está sempre na sua forma base, sem 'to'.

frontend.learn_grammar.from_rule: Dar conselhos e recomendações (Should)

Encontre e corrija o erro na frase.

Find and fix the mistake:

`If you are tired, you will go to bed.`

✓ Correct! ✗ Not quite. Correct answer: If you are tired, go to bed.
A segunda oração deve ser um imperativo (comando direto) 'go to bed', não uma previsão com 'will'.

frontend.learn_grammar.from_rule: Primeiro Condicional: Comandos e Conselhos (If + Imperativo)

Encontre e corrija o erro na frase.

Find and fix the mistake:

If she will arrive late, she should call us.

✓ Correct! ✗ Not quite. Correct answer: If she arrives late, she should call us.
Na if-clause do Primeiro Condicional, usamos o presente simples. Portanto, 'will arrive' está incorreto; o correto é 'arrives'.

frontend.learn_grammar.from_rule: Primeiro Condicional para Conselhos (should)

Escolha a forma correta para completar a frase.

You ___ remember your passport for international travel.

✓ Correct! ✗ Not quite. Correct answer: must
Must é um verbo modal e é seguido pela forma base do verbo principal, sem 'to' ou '-s'.

frontend.learn_grammar.from_rule: Must: Obrigação e Necessidade Fortes

Score: /9

Perguntas comuns (6)

'Should' significa principalmente que é uma boa ideia fazer algo, ou que algo é geralmente esperado. É usado para dar conselhos, recomendações e sugestões suaves. Pense nele como um empurrãozinho útil. Por exemplo:
You should try this!
Com certeza! Você pode usar 'should' para fazer auto-recomendações ou refletir sobre o que você acredita ser o melhor para você. Por exemplo: 'I should probably get some sleep' (Eu provavelmente deveria dormir um pouco) ou 'I should start that project soon.' (Eu deveria começar aquele projeto logo).
R: Must é usado principalmente para expressar obrigação forte, necessidade ou proibição. Pense nele como um 'requerido' ou 'não permitido' bem firme:
You must follow the rules.
R: Não, must é um verbo modal, o que significa que ele se comporta de forma diferente dos verbos regulares. Ele não muda de forma para diferentes sujeitos ou tempos verbais:
He must go, they must go.
É sobre dar conselhos ou fazer recomendações para uma situação real e possível no futuro. Você está dizendo:
If X happens, then you should do Y.
Um Primeiro Condicional normal com 'will' prevê um resultado (
If it rains, we will stay home
). Com 'should', você está oferecendo uma sugestão ou conselho (
If it rains, you should take an umbrella
).
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