–Would you mind _______ the yard?–OK. I’ll do it in a minute.

The victim was last seen ______ his office at 7 p.m.

We must do everything we can _________ our earth clearer and safer.

My teacher used to _______ a bike to school, but now he is used to ________ a car to work.

She saw a lot of boys ________ football on the playground when she walked past (经过).