A brilliant idea occurred to him, ______ to his research in the lab．
A．while devoting B．while devoting himself
C．while he was devoted D．while devoted
_____ it would be silly to argue any longer ．
A．Was that true B．If that was true
C．Should that be true D．Could that be true
Did ______ on time make the teacher angry ?
A．she not come B．she not to come
C．not her coming D．her not coming
You can hardly imagine the difficulty the woman had ______ her children．
A．brought up B．to bring up
C．bringing up D．to have brought up
Only one of the places is ________
A．worth to visit B．worth visiting
C．worth of visiting D．worth being visited
-- Has Mr. White arrived?
-- Yes, already, _______ he wait outside or just come in?
A．Shall B．May C．Could D．Must
