Where is your mother?— She has ______ to Sichuan on business. She has ______ there four times recently.

Many birds are out of ____________ now, because we have done a lot of things to protect __________ birds.

This is our __________ Chinese lesson.

In our city, _______ middle school students want to work as a teacher in the future.

Look, my father bought me a new iPad.—I don’t think we need too many expensive things even though our parents can ______them.