-- _____ classes are there in your school?   –Thirty. 

I don’t like physics ______ it’s too difficult for me.

—What do you think of Cindy? —Oh, kind and helpful.          I do, she always gives me advice and help.

 He didn’t tell me the truth _____ I met him in the street.

 Tom’s a taxi driver, ＿＿＿＿＿ he really wants to be a singer.