I ______ on a maths problem when he telephoned me early this morning.
A: [A] had worked
B: [B] was working
C: [C] have worked
D: [D] have been working
A: [A] had worked
B: [B] was working
C: [C] have worked
D: [D] have been working
举一反三
- They ______ on the program for almost one week before I joined them. A: had been working B: bad worked C: have been working D: have worked
- By the end of last week, he ________ in the company for 10 years. A: had worked B: had been working C: will have worked D: would have worked
- By the end of last year, I ______ in this college for ten years. A: have worked B: had worked C: worked D: have been working
- I am tired. I ______ all day. A: am working B: have been working C: worked D: have been worked
- I first met Mary three years ago when we ______ in a middle school together. A: have worked B: had been working C: were working D: had worked