The students are to submit their final assignments by the end of this month. are to submit in this sentence shows….

I had to wait five minutes on the line _____________ him.

I went to the post office _____________ some stamps.

You must do your homework before you can go out. The underlined words can be best replaced by________

What are you going to do if we refuse ______________ you?

The registration form needs ____________ completely by the participants.