How to create enough jobs for the laid-off workers is a(n)________problem for which there is no simple solution.

She looks very happy.She________have passed the exam.—I guess so.It’s not difficult after all.

I saw Mr Li at the meeting yesterday.— Did you He _______ have attended it, forhe had asked for sick leave.

The moonlight came in the windows in the roof and lit up my room.

This house looks strange to me There is something unusual with it [ ]