下面句中的“之”用法与其他三项不同的一项是(      )。

阅读理解,判断对错。

Tom：Excuse me，how do I get to the Ping'an Park ?

Woman: 1. go, you, can, by, there, bus . Or you can go on foot.

Tom: 2. How do I go there on foot ?

Woman: It's easy. Turn left at the traffic lights. 3.公园挨着一个博物馆。

Tom: Thank you very much. Hurry up, Zhang Peng!

Woman: No! The light is red. Stop!

Tom: That's right. We have to wait.

—Before he went on the stage，he took a deep ______ ．

    —He was too nervous．

①溶液质量增加         ②溶质质量增加    ③溶剂质量不变

④晶体质量不变         ⑤晶体质量减少