The imperative π

We use the imperative to give instructions, orders, warnings and advice.
Form: the base form of the verb, with no subject
Open your books.
Sit down, please.
Turn left at the bank.
Negative: don't + base form
Don't touch that!
Don't be late.
Let's: suggestions for you and me
Let's go!
Let's not argue.
Be polite
The imperative can sound rude. Add please, or use a question:
Please close the door.
Could you close the door, please?
π‘ In recipes, manuals and signs, the imperative is normal and polite: Mix the flour and the eggs. Press the green button.