that引导什么从句可以省

My teaching style is similar to that of most other teachers.

我的教学风格和多数教师相似。

Keep going like that ─ you're doing fine.

就这样做下去——你做得蛮不错嘛。

She's a changed woman since she got that job.

她自从得到了那份工作，变得判若两人。

That must be her now.

这会儿一定是她了。

It's the fifth time that I've been to America.

这是我第五次去美国了。