When __________ such a difficult problem, he didn't know what to do.
They are talking so warmly and it looks ___ they had been old friends.
. Nowadays people attach importance _______ the children’s pre-school education.
Mike wasn’t at home yesterday. He ______to give us a lecture.
A new bridge ______ across the river and it is expected to open next year.
We appreciate ______ us know the change of the date for the meeting.