Question

But how to do this.请问这是个完整的句子吗?如果是,请说出各部分的成分/结构.如果不是,请说下缺少了什

Answer 1

这不是个完整的句子.但口语中所用的句子常常并不完整.

书面来说,这句应该是：

But how do you do this?

But how is this done?

But how would you do this?