The pressure _______ causes Americans to be energetic,but it also puts them under a constant emotional strain.
问题描述：
The pressure _______ causes Americans to be energetic,but it also puts them under a constant emotional strain.
a、to compete
b、 competing
c、 to be competed
d、 haveing competed
the pressure to do something
为什么选A
答
the pressure to do something 做某事的压力
竞争压力使美国人富有活力,但也使他们长期紧张.
（意译）