Mrs. White became a teacher in 1985. She _____ for twenty years by next summer.

A. will teach    B. would have taught    C. has been teaching    D. will have been teaching

Mrs. White showed her student some old maps _________from the library.

A. to borrow??????? B. to be borrowed

C. borrowed?????? D. borrowing

Just after putting the baby onto bed, Mrs. White suddenly caught sight of the pet cat and didn’t know how long it________ on the table for the family dinner.

A. had been laying; lying    B. had been lying; laid

C. had been laid; laid       D. had lain; laying

---We really enjoy ourselves at the party. Thanks again, Mr. and Mrs. White.

---_____. Just drop in whenever you feel like it.

A．Our great honor                        B．Nice having you here

C．Nice you are here                       D．With pleasure

Mrs. White was so ________ in her work that she didn’t notice a stranger enter the office.

   A. absorbed    B. adjusted    C. focused    D. centered