—I’ll go camping this weekend．

—      

    A．Best wishes．                        B．No，I'm too busy．

    C．Don’t give up now．                 D．Have a good time．

 — These days I can only sleep for four or five hours at night as I’m too busy with my research work..

   — If you keep going on like that, you are sure to ______ sooner or later.

     A. get down         B. break down       C. calm down      D. put down

—Would you like to come up to my apartment for dinner tonight?

—_____, but I’m too busy.

—Would you like to come to dinner tonight？

    —I’d like to, ___ I’m too busy.

    A. and ...B. so

    C. as...D. but

—Excuse me, may I ask you some questions?

   ---Sorry, I’m too busy and haven’t even a minute to________.

A. spend    B. spare    C. share   D. stop