Have they swept the floor yet?
No, they haven't swept the floor yet.
Have you made a cake yet?
Yes, I've already made a cake.
Has he served the drinks yet?
No, he hasn't served the drinks yet.
Has she made the posters yet?
No, she hasn't made the posters yet.
Have you gone shopping yet?
Yes, I've already gone shopping.
Have we decorated the room yet?
Yes, we've already decorated the room.
Has she cleaned the furniture yet?
No, she hasn't cleaned the furniture yet.
Have they put out the food yet?
Yes, they have already put out the food.
Has he blown up the balloons yet?
No, he hasn't blown up the balloons yet.