To allow teenagers to study in groups during the evening is

To allow teenagers to study in groups during the evening is a good way.改为同义句
It's a good way ___teenagers to study in groups during the evening
这里for和to allow

It is a good way to allow teenagers to study in groups during the evening.
可以,只是意思是有点不一样了
for 对于青少年来说,在晚上学习是个好法子
to allow 允许青少年在晚上学习是个好法子
所以,如果改成同义句的话,不能用for,而要用to allow
再问： 对，我的意见和你非常相似，这句话说的事一个由to引导的方法，但是答案是for
再答： 汗哦，这什么试题啊，出题的脑子不好使，短路了，嘿嘿