问题
完形填空
They prepared manmade rubber as a substitute________ the natural rubber that they could no longer obtain.
答案
for
句意：他们用人造橡胶替代无法再获取的天然橡胶。substitute“代替品”后接for，与句意相符。
搜题请搜索小程序“爱下问搜题”
They prepared manmade rubber as a substitute________ the natural rubber that they could no longer obtain.
for
句意：他们用人造橡胶替代无法再获取的天然橡胶。substitute“代替品”后接for，与句意相符。