This meaning is about giving permission or saying 'yes' for something. You use it when you allow someone to do an action.
Please let me help you now.
She lets him play outside.
Here, 'let' means to allow a condition or event to happen. You use it when you don't stop something or you cause a change.
Let the water boil for ten minutes.
Let the door stay open.
In this business meaning, 'let' means to give a house, room or something for someone else to use, usually for money.
They let the flat to new tenants.
I let my car during the holidays.
'Let' can mean to not stop something from happening. It often means you allow a bad or unwanted thing by accident or mistake.
He let the secret slip out.
Don't let the dog escape.
As a noun, 'let' means a small problem or delay that causes you trouble or stops something from working well. It is often used in formal or British English.
There was a let in our plans.
Traffic was a big let today.
In sports like tennis, a 'let' means players must play the point again because something interrupted the play. It is a special rule term.
The umpire called a let in the match.
There was a let because of the noise.
You can use 'let' to say you allow someone to come in a place or go somewhere. It means giving permission to enter or pass.
He let me in the house.
Please let us through, thanks.
'Let’s' is a short form for 'let us'. We use it to suggest doing something together. It is very common in everyday conversation.
Let's go to the park now.
Let's eat lunch together today.