Miss Zhao is very helpful． She often helps us we are in trouble．（ ）
| A． |
whether |
B． |
although |
C． |
whenever |
D． |
however |
﹣ Bi Sheng， an ancient Chinese， inventedmovable type printing in the 1040s．
﹣ It was developed in China but served the world．（ ）
| A． |
created |
B． |
discovered |
C． |
searched |
﹣ You are always there for me when I am in trouble．
﹣ That's what a friend should do．（ ）
| A． |
in fear |
B． |
in difficulty |
C． |
in surprise |
﹣ Your English teacher is very humorous．
﹣ Exactly． She is very popular with us．（ ）
| A． |
friendly |
B． |
outgoing |
C． |
funny |
﹣Tom， let's go to play basketball．
﹣ I'd love to． But I have to completemy homework first．（ ）
| A． |
check |
B． |
finish |
C． |
correct |
—The air pollution is terrible．
—It will be worse________we take action to protect the environment．
| A．if |
| B．unless |
| C．until |
| D．when |