帮忙看哪句句子对,为什么

第二句对

这是动词不定式做后置定语的用法
我们还原
live new planet 和 live in new planet
你觉得哪个对？
明显，是live in ，
所以，你只要记住适当的时候，还原，就好了

再跟你说几个常考的

the pen to write with
还原，write with the pen

the man to talk with
还原，talk with the man

We can't find new planet to live. 对

We can't find new planet to live in对

We can't find new planet to live. 对
"to"作为介词, 后面应该跟动词

We can't find new planet to live in.
这个是对的，你可以对照
We live in the earth.
We can't live in a new planet.
采取这种类比的方法会比较好。