国内水路运输的缺点有( )。
A．成本较高
B．运送速度慢
C．受自然条件影响较大
D．安全性较低
E．水网覆盖面较小
参考答案：B,C,D
——John always thinks of others instead of himself.
—— So he does. It is _______ of him to want to help others.
A．aggressive
B．conventional
C．evident
D．typical
The writer was _____ in his writing that he forgot to flick the ashes from his cigar.
A concentrated B devoted C absorbed D fixed
