The farm ____ we visited yesterday is located in the suburb

因为从句中没有介词,所以加which不完整,需要加一个介词,可以用where代替

D

根本没有at that 的用法
所以,at which=where你能理解,其他就没什么问题了
定语从句有三不法
没有what how引导,也没有介词加that 的用法

A

The student wants to make a visit to the farm.

A
定语从句,that 代替the farm 做see 的宾语,we see the farm（that）,而where不能做see 的宾语,淘汰BC.
定语从句中,如果先行词时the one,那么关系代词只能使用that,不用which,淘汰D

Where do you want to go?

was
yesterday 代表过去时,farm是单数,用is的过去时态,was

The farm (that) we see today is no longer (what) it was ten years ago

In some countries,there are children who are educated by their parents at home instead of being taught by teachers at school.Do you think this is a good or bad idea?Think of its advantages and disadvantages.
With the development of society,it is more easy and convenient for us to study home by ourselves.And many parents educate their children at home instead of at school.There are advantages and disadvantages for both ways.
The main reason why parents choose to teach their children at home is that it is a good method to teach students in accordance with their aptitude.For every child has different hobbies and talent,teaching them at home can help them find and develop their being genius effectively.
On the other hand,the healthy overall development of a child attributes to many integrated factors.Some extracurricular activities are beneficial supplement to be classroom instruction.And if children are encouraged to attend only academic activities,their overall development will inevitably be hindered.Their individualities and originalities will undoubtedly be impaired,because our society a diversified one.Children should be encouraged to get in touch with various aspects as society to attain a more comprehensive knowledge.
So in my opinion,it is better to teach children by teacher at school

on 在农场是on,固定搭配,记住就行

there were any fruit trees on the farm?

首先,what不能引导定语从句,排除A
若主句中有such或主句中有the same时才可用as,排除C
只有以下五种情况可省略先行词
1.在从句中充当宾语
2.在从句中作介词宾语,且介词在句尾
3.在从句中作表语
4.在There be句型中,作主语的关系代词
5.先行词是表示方式,原因,时间（像way,reason,day),in which,for which,when,that等可省
所以D也不符合
故选B
但我个人就得B选项应该是on which或where吧
o(∩_∩)o...哈哈我也是学生,我是这么理解的