to be + 形容词 与直接用 形容词 有什么区别?
The teacher asked the students to be quiet.

Modern telecommunications have had a dramatic impact on our mobility similar to the invention of the automobile or the train.
与汽车或者火车这两项发明一样,现代通信对我们的流动性产生了极大影响.

to be quiet和直接用similar 好像都是对的?

为什么这里不是 being similar 或者 to be similar