The river has become much ______ than before because of the waste water.
A. dirty B. dirtier C. Dirtiest
----Do you know how the accident _______?
----Sorry, I don’t know.
A. come out
B. come into being
C. come about
-----I wish I _____ go into space some day.
----- I hope your dream _____ true.
A. could , will come
B. can , came
C. can , will come
_____ my father ______ my mother take good care of me. I love them so much.
A. Either; or B. Both; and C. Neither; nor
—Hi, Jane, tell you a piece of good news. I _____ America tomorrow.
—Wow, have a good trip!
A. will leave to B. leaves for C. am leaving for
-- Hello, may I speak to Mr. Smith?
-- Sorry, he isn't in. He ______the office.
A. has been to
B. has gone to
C. has been away
