Good teachers can usually give the students______ advice on their study.

I have to well prepare for the math test tomorrow because it ______ 30% of the final exam.

Sandy,I called you at 9:00 last night,but nobody answered the phone.-I’m sorry. We ______ a birthday party _______ Jerry.

I’m afraid I can only make a small contribution this time.—____.We really appreciate your assistance.

Whose sweater is this? —It looks like John’s. Oh, yes. It’s __________.