I don't have a room to live in /There is no seat to sit on the bus两句为什么要有to?I don't have a room live in /There is no seat sit on the bus不可以吗?

I don't have a room to live in /There is no seat to sit on the bus两句为什么要有to?I don't have a room live in /There is no seat sit on the bus不可以吗?
I don't have a room to live in /There is no seat to sit on the bus两句为什么要有to?I don't have a room  live in /There is no seat  sit on the bus不可以吗?

I don't have a room to live in /There is no seat to sit on the bus两句为什么要有to?I don't have a room live in /There is no seat sit on the bus不可以吗?
如果是这样的,I don't have a room live in /There is no seat sit on the bus.
先看第一句,里面有have 这个实义动词和live这个实义动词,是不行的,因为语法讲究一句话里面必须只有一个谓语动词.
第二句,is是be动词,sit on是实意动词词组,所以有两个谓语动词是不允许的.
只好加to变成不定式形式,就是一个没有语法错误的句子了.明白吗?

楼上正解

语感好也挺重要的。

确实没to语感不顺啊