—How long has your brother _________ in the army ?—About five years.
— do you tell him about the news? —By an e-mail.
I used to to school by bike, but now I am used to to school.
There are some dangerous fishes in this river, and I’ve warned Jack here.
Chinese students often give small gifts or cards to their teachers on Teachers’ day to let them know _____. A.how great they are B.how great are they C.what great they are
Tom found _____ difficult to learn chemistry well. A.it B.that C its