Early in the ancient times, farmers did experiments(improve)______ the agricultu

游客2023-10-01 28

问题 Early in the ancient times, farmers did experiments(improve)______ the agricultural productivity.

选项

答案 to improve。

解析根据句子结构判断，空格处应为动词不定式作目的状语，所以空格处应填入improve对应的动词不定式形式to improve。

转载请注明原文地址:https://tihaiku.com/zcyy/3063044.html

相关试题推荐

随机试题

最新回复(0)

Jackcalledtheairlineto______hisflighttoBeijingthismorning.A、improveB、