—Look, John’s fallen asleep.

— Oh, he _______ too late last night.

A. might sit up     B. should have sat up      C. could sit up           D. must have sat up

 —Look, John’s fallen asleep.

— Oh, he _______ too late last night.

A. might sit up     B. should have sat up      C. could sit up       D. must have sat up

Look, John's fallen asleep.

Oh, he ________ too late last night.

[　　]

- Look, John's fallen asleep.

　 - Oh, he ________ too late last night.

　 A. might sit up　　　　　　　　　　　　 B. should have sat up

　 C. could sit up　　　　　　　　　　　　 D. must have sat up