The weather is too dry.Those trees need________.
When the first settlers came to North America, they had to ________ the forest and found a way out.
—I'd like to go camping with you, but I have meeting _______. —If you don't go, ______.
—Why are the lights in the teachers’ office still on? —There ________ be some teachers working there.
—What are people supposed to do when they meet for the first time in China? —They are supposed to _______.
—This article is too hard to understand. —Yes, _______ it's very short and there are few new words in it.