完形填空.some are unpleasant to our ears {while} others are {very pleasant} to hear.

问题描述:

完形填空.some are unpleasant to our ears {while} others are {very pleasant} to hear.
为什么while 不能用when.very pleasant 是什么用法为什么不能用much pleasant

while有表转折的意思.但是when没有.一般没有much pleasant这么说.more pleasant就有.因为pleasant是多音节词.如果用到比较级就得用more.但是这里没有比较.所以用very就可以的.