this是什麼意思漢語

例句：

This will be a problem for some time to come.

這將是未來一段時期裏的一個問題。

This is the one major drawback of the new system.

這是新系統的`一大弊端。

This is one of the most commonly used methods.

這是最常採用的方法之一。

It's about this high.

大約有這麼高。

The number of new students decreased from 210 to 160 this year.

今年新生人數從210減少到160。