— You look tired.

— Yes. I ___ non-stop until 8 o’clock.

A. had worked         B. work        C. have worked       D. was working

— You look tired.

— Yes. I ___ non-stop until 8 o’clock.

A. had worked         B. work           C. have worked       D. was working

—You look tired.

—Yes,I     non-stop until 8 o'clock.

A.had worked  B.had been working   C.will work   D.was working

— You look tired.

— Yes. I ___ non-stop until 8 o’clock this morning.

A. had worked         B. work            C. have worked       D. was working