Jane’s dad is getting old, so she has go back home to see him ______ it’s convenient.

ccording to recent reports, one ofthe rare animals, _______ crocodile, will be in danger of dying out in _____2020s.

Look at that red car! I think it’sinthe world.

What should we ____________ in class We should pay attention ___________ notes when necessary.

You ______be sitting in this waiting room, sir. You see, it is for women and children only.