—Is Mrs. White in the office?—Yes, ___A__ she is on duty, she must be there.
A: since
B: until
C: while
D: if
A: since
B: until
C: while
D: if
举一反三
- The little girl didn’t go to bed ( ) she was asked to .. A: while B: until C: since D: as soon as
- Mrs. White has _____ that she is not able to get a job.
- Mrs. White asks the cashier ________ she should pay.
- —I think Miss Gao must be in the library. She said she would go there. —No. She __be there, I have just been there.
- She didn't realize it was too late to go home（）it grew dark. A: while B: since C: until D: after