The boss has given everyone a special holiday, so they      go to work tomorrow .

I have two brothers. One is a teacher, _________ is a doctor.

— Wow! You look different! You            wear glasses.— Yes, I did. But now I am wearing contact lenses(隐形眼镜).

—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?

–Look at that girl! Is it Susan? --No, it _______ be hers. She has gone back to her hometown.