Instructions, Don’t and Let’s
Short answer: To tell someone what to do, start with the plain verb: Sit down. To say what not to do, use Don’t: Don’t run. To suggest doing something together, use Let’s: Let’s play. Add please to be polite: Please sit down. Sit down, please. The subject is you, so you do not say it.
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At a glance
| Use | Pattern | Example |
|---|---|---|
| tell someone to do | verb | Open the door. |
| tell someone not to do | Don’t + verb | Don’t run! |
| suggest together | Let’s + verb | Let’s go to the park. |
| be polite | please | Stand up, please. |
In short
- Start with the action word to give an instruction.
- Don't + action word means stop. Let's + action word means do it together.
- Add please to be polite.
What is the rule for “Sit down! Let's play! Instructions and Let's”?
The rule
Start with the action word to tell someone what to do. Use Don't to stop them. Use Let's to do it together.
How it looks
Sit down. · Don't run. · Let's play.
What it means
They give an instruction or a suggestion.
When to use it
Add please to be polite.
How it works
- For an instruction, start with the plain verb. Do not add you or to.
- To say no, use Don’t and the plain verb.
- To suggest, say Let’s and the plain verb. It means let us.
- Add please at the start or at the end to sound polite.
Examples of “Sit down! Let's play! Instructions and Let's”
- Open the door.
Start with the action word. - Don't run!
Don't + the plain action word. - Let's go to school.
Let's + the plain action word. - Stand up, please.
please makes it polite. - Close your book.
Start with the verb. The subject is you. - Don’t touch the stove!
Don’t + the plain verb. - Let’s have lunch.
Let’s + the plain verb. - Please be quiet.
Be is the verb here. Please makes it polite.
Common mistakes with “Sit down! Let's play! Instructions and Let's”
Don't runs!→ Don't run!
After Don't use the plain action word.Let's to play.→ Let's play.
No to after Let's.Not touch!→ Don't touch!
Use Don't to say do not.You sit down!→ Sit down!
In an instruction, start with the verb.Not talk!→ Don’t talk!
Use Don’t to say do not.
Exceptions: watch out
- please
please can come first or last: Please sit down. Sit down, please.
Instruction, request or suggestion?
Three different jobs use similar forms. Choose by the situation.
| Job | Form | Example |
|---|---|---|
| instruction | verb | Open the window. |
| polite request | Please + verb / Can you...? | Please open the window. |
| suggestion | Let’s + verb | Let’s open the window. |
See also: Polite talk: Can I …? Would you like …?
Check yourself
- Make it negative: “Run in the room.”
Show the answer
Don’t run in the room. Don’t + the plain verb.
- Suggest: play football together.
Show the answer
Let’s play football. Let’s + the plain verb.
- Fix: “Let’s to go.”
Show the answer
Let’s go. No to after Let’s.
How to practice “Sit down! Let's play! Instructions and Let's”
The interactive version adds step-by-step help, spoken instructions and a quick check. One rule card, one sound lesson and the first lesson of every stone are free to try; the rest is part of Full Access. See Full Access.
- Practice lesson: Sit down! Let's play! Instructions and Let's
Questions
Is it rude to give instructions without “please”?
Not always. In class, signs and recipes, short instructions are normal. With people you do not know well, add please.
Is “Let’s” the same as “Let us”?
Let’s is the usual short form for a suggestion. Let us is formal.
Can I use “Don’t” with “be”?
Yes. Don’t be late. Don’t be afraid.
More Sentence Building rules
- Subject + Verb: A sentence needs someone or something (the subject) and a verb: Birds fly.
- Verbs can have an object: Some verbs can have an object: the person or thing that gets the action.
- Present simple: I, you, we, they: For things we do again and again, and for likes, use the plain action word with I, you, we and they.
- Present simple: he, she, it + -s: With he, she, it or one name, the action word usually adds -s.
- Negatives: not with be and can: To say no with am, is, are or can, add not: I am not, she isn't, they aren't, it can't.
- Negatives: don't and doesn't: To say no with an action word, use don't or doesn't and then the plain action word.
Part of the 📘 Grammar tool. Level G2: Sentence Building. Đọc bằng tiếng Việt.
Written for English learners by the English for Fun team. How we write our lessons · Last updated 2026-11-05.
Reviewed by Chinh Q. Hoang, PhD, founder, English for Fun · 2026-10-30
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