We often use an imperative in commands, and we also use must. They both sound very direct:
Stop talking now!
[a father to his child]
Don’t press that button.
[a mother to a child]
You must wear a coat. It’s raining.
There are a number of ways of making commands sound more polite. We can add please at the end of what we say, or we can use a question form to make a command sound more like a request, or we can use I’d like you to + infinitive or I’d be grateful if you’d + infinitive without to:
[a boss to an assistant]
Ask Max to sign this form and then send it off immediately please, Gwyn.
Will you bring us the files on the Hanley case please, Maria?
I’d like you to bring us four coffees at eleven when we take a break in the meeting.
I’d be grateful if you didn’t tell anyone about this.
Public notices often give direct commands using no, do not or must:
We use instructions to tell someone how to do something. We usually use imperatives. They do not sound too direct in this context:
[a cookery class]
Beat four eggs, like this. Then add the flour gradually. Don’t beat the eggs too much though.
[instructions on how to replace a missing button]
Thread your needle with a piece of thread about 25 cm long. Mark the spot where you want the button. Insert the needle from the back of the fabric and bring it through …
In speaking, we often use the present simple when we are giving instructions and demonstrations, and we say like so meaning ‘like this’:
You fold the A4 piece of paper like so. Then you glue some shapes onto this side and sprinkle some glitter on it like so.