18.--- Tom has a lot of parties recently.---Yes, that may ____ why he didn’t do well in the test.A, sum up B. add up to C. account for D. make sense of
—Do you like ______ here? —Oh, yes. The air, the weather, the way of life. Everything is so nice.
The chairman thought necessary to invite Professor Smith to speak at the meeting.
No progress was made in the trade talk as neither side would accept the conditions of .
Ten years ago the population of our village was_____that of theirs.
The CDs are on sale!Buy one and you get ______ completely free.