It's dangerous to let the children who are__go swimmingA.so young toB.so youngC.not old eough toD.too young towhy choose
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
答
It's dangerous to do..做什么事情很危险。
let the children go swimming. 让这些孩子去游泳。（Let sb. do sth.句型）
因此，It's dangerous to let the children go swimming.让这些孩子去游泳是很危险的一件事。
who are so young修饰the children,表示这么小的孩子。
整句话就是，让这些这么小的孩子去游泳是件很危险的事。
答
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!