eople volunteered to donate blood; however, the blood bank needs ________.

These teenagers don’t know much of the world yet; that’s why they are so easily _________ .

John has determined to _______ teaching in the quake-hitarea when he graduates from university.

So many problems! I’m tired.—You should try to them by yourself. You are not a child any longer.

I’m sorry I didn’t phone you, but I’ve been very busy____ the past couple weeks