Last year, I visited a chemical factory in Baise, there are about _____ workers in it.

The old man never fails to help___ is in need of his help.

In 2000, we ____ to the Great Wall and had a good time there.

Claudia, are you going to Jeff’s birthday party on Saturday?-Unless I______ .

Whose tennis racket is this, Linda?–Look! Jerry’s name is on it! It _________ be his.