单项选择题

Steamboats began to sail up and down the Mississippi River at the beginning of the 19th century, which contributed a lot the areas along the river.

A．to develop
B．to being developed
C．to be developed
D．to developing
<上一题 目录 下一题>
热门 试题

单项选择题
I regretted ______the expensive air-conditioner.
A．not to afford
B．not affording
C．not being able to afford
D．I can't afford
单项选择题
The puppet power only survived the riotous (造反的) officer ______.
A．with six days
B．by six days
C．during six days
D．in six days
相关试题