About 15 years ago, scientists did many experiments (develop) _____ the tools to

游客2024-07-03 50

问题 About 15 years ago, scientists did many experiments (develop) _____ the tools to detect new planets.

选项

答案 to develop

解析本题考查动词不定式。do sth．to do“为了……做某事”。

转载请注明原文地址:http://tihaiku.com/zcyy/3660539.html

相关试题推荐

随机试题

最新回复(0)

Scientiststhinkthedifferencebetweenanimalsandmenis______.[br]Now,sci