16. If the fire alarm is sounded, all residents are requested to _____ in the courtyard.
A. converge
B. assemble
C. crowd
D. accumulate
17. If the United States had built more homes for poor people in 1995, the housing problems now in some parts of the country _____ so serious.
A. wouldn't be
B. wouldn't have been
C. will not be
D. would have not been
18. If Tom wins tomorrow, he _____ thirty races in the past four years.
A. will win
B. has won
C. would have won
D. will have won
19. If we believe something is good and true we should _____ to it.
A. hold up
B. keep on
C. hold on
D. keep up
20. If you _____ James, ask him to phone me.
A. should see
B. must see
C. might see
D. would see