第二节：短文改错(共10小题；每小题1.5分，满分15分)
注意：原行没有错的不要改。
A helicopter is sometime more useful than a big plane. When　      11＿＿＿＿＿＿
it takes off, it goes straight on. When it lands, it comes             12____________
straight down. It needs not only a small place for both taking        13 ___________
off and landing. When a tall building is on fire, we can             14____________
see a helicopter to come down to rescue the people on the top        15 ___________
of them. Helicopters make many kinds of work easy. They are        16____________
used to making maps, flying over the ground and taking pictures     17____________
from the air. To rescue people whom are very                     18____________
sick or in danger, helicopters are send to some faraway            19____________
areas. The helicopter takes place of a car or a train                20____________
in some areas.