anthropologists是studying的逻辑主语.如果要用study,就要改成When anthropologists study different cultures and societies.
这里显略了它的主语,而study与逻辑主语之间是主动关系,所以用studying.
如果study与逻辑主语是被动关系,就要用studied.
anthropologists是studying的逻辑主语.如果要用study,就要改成When anthropologists study different cultures and societies.
这里显略了它的主语,而study与逻辑主语之间是主动关系,所以用studying.
如果study与逻辑主语是被动关系,就要用studied.