Question

帮忙改个错~~

As many average people begin to pay more attention health, the amount of people who go to this gymunasium has increased in quantity. So the boss of this gymunasium decide to build a new layer, and then he has to make up for closing.

Answer 1

As many average people begin to pay more attention（加个to） health, the amount of people who go to this gymunasium（单词拼写错误，应该是gymnasium ） has increased in quantity. So the boss of this gymunasium（gymnasium ） decide（decides) to build a new layer, and then he has to make up for（加个the)closing.

另外：the amount of people who go to this gymunasium has....中除拼写错误，其他都是正确的。
因为people是集合名词，amount意为“数量，总数”，the amount of 修饰people是没有问题的，而has修饰的主语是amount ，用单数也是没有问题的，其他几位想错了。。。
下面给你几个类似的句子：（词典上的例句，100%正确，看了就明白了）
The amount of his remarks is that ...
他的话总的意思是...
The amount of unemployed capital is very large.
未被利用的资金数量很大。

closing是歇业的意思，因为越来越多的人开始注重健康，来健身馆的人总数大量增加，所以老板决定新建一个楼层，然后他不得不对（重建期间造成的）歇业进行补偿。

Answer 2

pay attention to 是固定搭配 所以要加to amount 改为 number 因为人的数量是可数的都用它来表示 因the boss是单数因此谓语动词要用decides

Answer 3

把gymunasium后面的has改成have

Answer 4

As many average people begin to pay more attention TO health, the amount of people who go to this gymnasium has increased in NUMBER. So the boss of this gymnasium decideD to build a new LEVEL, and then he has to (make up for closing).

Not sure what you intended to say... (make up for closing?)