万一她回来了。英语怎么说

in case she comes back. 这不是一个完整的句子，但几乎可以加载任何完整句子的开头或结尾。记得用逗号隔开。

What if she comes back? 意思是： 万一她回来了怎么办？

根据你的提问来看，估计只是想问一句话中出现的，万一她回来了，怎么怎么样，一般用 In case she comes back,

例如：万一她回来了，让她等我
In case she comes back, ask her to wait for me

What if she comes back?

Incase she comes back.