Mr. Green didn’t post the letter _________. He asked his son to do it for him.
—How is the weather in Shanghai? —______.
Let’s clean the classroom. It’s very ______.
—____ does he like pandas? —Because they are cute.
—Where is your school? —It is ______ the bank.
—Hello, Betty. Is your mother a teacher? —No, she is a doctor in a _____.