The United has studied the possibility of having people (to) live beneath the ocean.这句里面为什么加了To是错误的?In order to attain our objective ,it's essential that we (will) make the best use of the limited resources available.这句

The United has studied the possibility of having people (to) live beneath the ocean.这句里面为什么加了To是错误的?In order to attain our objective ,it's essential that we (will) make the best use of the limited resources available.这句
The United has studied the possibility of having people (
to) live beneath the ocean.这句里面为什么加了To是错误的?
In order to attain our objective ,it's essential that
we (will) make the best use of the limited resources available.
这句里面为什么不能加上will?
As people approach (to) old age,their energy may diminish.
不带to的原因?
Now that he is working much harder ,I don't think he'll have
any trouble (to pass) the entrance exams!
这里的to pass为什么会用 passing才对
Let's not waste time no matter of no (important)!
这里的important 为什么是importance?
希望列举一些如：Be+adj
介词+动词原形
.
诸如此类的简单语法!
只有这么多分了
全给了
.

The United has studied the possibility of having people (to) live beneath the ocean.这句里面为什么加了To是错误的?In order to attain our objective ,it's essential that we (will) make the best use of the limited resources available.这句
The United has studied the possibility of having people (to) live beneath the ocean.这句里面为什么加了To是错误的?
have sb do sth--固定用法,让某人做某事
In order to attain our objective ,it's essential that
we (will) make the best use of the limited resources available.
这句里面为什么不能加上will?
习惯用法,it is essential that sb do sth--虚拟语气,省略中间的should或者类似的词.
As people approach (to) old age,their energy may diminish.
不带to的原因?
approach做接近的意思讲的时候是及物动词,不需要加介词,做靠近讲的时候是不及物动词,需要加介词才能加宾语,这里是说接近老年的时候,所以不用加介词.
Now that he is working much harder ,I don't think he'll have
any trouble (to pass) the entrance exams!
这里的to pass为什么会用 passing才对
have trouble doing sth/have trouble in sth固定用法.
Let's not waste time no matter of no (important)!
这里的important 为什么是importance?
be of importance=be important
希望列举一些如：Be+adj
太多了--be nice,be cool,be brave.
介词+动词原形
不确定
.
诸如此类的简单语法!