It's dangerous to let the children who are__go swimming

问题描述:

It's dangerous to let the children who are__go swimming
A.so young to
B.so young
C.not old eough to
D.too young to
why choose

Let somebody do sth,而不是Let somebody to do sth.
who are so young 这个主语从句是用来修饰the children的,如果把这个主语从句去掉,只剩下Let句型,就是Let the children go swimming,这句话是正确的,如果选择A,就成了Let the children to go swimming,这与Let句型不符.然后C,D答案很明显是不正确的!所以选择B!