all of,all; both of,both他们分别有什么用法上的区别

all of them

all the students

Both of you

both are happy

具体也不好说区别 都通用
看看例子可能就明白了

all of (3个以上)意为所有的...
all (同上)意为所有的
both of (2个)意为...中的两个
both (同上)意为两个都