Do you think it necessary to learn to wait in line 我总是觉得it 要变成it is

Do you think it necessary to learn to wait in line 我总是觉得it 要变成it is
Do you think it necessary to learn to wait in line 我总是觉得it 要变成it is

Do you think it necessary to learn to wait in line 我总是觉得it 要变成it is
变也可以,但句子结构也变了,一般情况都是用第一句.
Do you think it necessary to learn to wait in line .简单句
Do you think it is necessary to learn to wait in line 宾语从句

Do you think (that) it (is ) necessary to learn to wait in line , it作主语时that和be动词可以同时省略
记得初中时有一篇文章里有一句I found it very difficult to get to sleep,牢记一句话，以后就不会犯错了

都正确
一个是形式主语
一个是形式宾词