1.there are five pairs ______ ,but i am at a loss which to buy.

问题描述:

1.there are five pairs ______ ,but i am at a loss which to buy.
A to be chosen B to choose from C for choosing
我知道为什么选B 但我想知道不能选AC的原因
2.what surprised me was not what he said but ______ he said it.
Athe way Bin the way that C in the way
我也懂得选A 但我想听听怎么解释不能选BC

逻辑主语是I所以是to choose主动的.i am at a loss which to buy.
说明只买一个.所以是从5个里面选一个.就这样
the way he said it.是定语从句.可以写成the way that/in which he said it.