—The research on the new flu virus vaccine is challenging and demanding. Who do you think can do the job?     —______ my students have a try?

--Why didn’t you come to Simon’s party last night?---I wanted to, but my mom simply _________ not let me out so late at night.

—Is it necessary to look up every new word when I come across it in reading?—No. You ________， because you are likely to guess the meaning from the context.

— Catherine, I have cleaned the room for you . — Thanks. You_______. I could manage it myself.

(2013·高考北京卷)—You needn’ t take an umbrella.It isn’t going to rain.—Well，I don’t know.It________do.