—Did you call on any of your old friends when you returned to your hometown?
—_______ of them. They were all very busy.

Some don’t agree to the plan, while I’m out of ____ opposed to it.

You may depend on ____ that they are of much value.

Cars do cause people some health problems, in fact far more serious _____ than computers do.

The field research will take Joan and Paul about five months; it will be a long time _________ we meet them again.

With the rapid development of the Internet, _______ communication is done by regular mail.

—Who knocked at the door?
—I’ve no idea. I just pretended nobody was at home, so I didn’t ask who ____ was.