我们说道,引导定语从句的关系代词指人时要用who 或that;指物时要用which 或that。who 与which 一个明确指人,一个明确指物,两者一般情况不可互换。但在下列情况下关系代词既可用who,也可用which,一般说来,所表示的意思仍有区别。1.当先行词是baby,child,或boy 时This is the baby which needs inoculation.这就是那个需要打预防针的婴儿。 We said that the relative pronouns that guide the attributive clause should use who or that when referring to a person; which or that should be used when referring to an object. Who and which are clearly referring to a person, a specific thing, the general situation is not interchangeable. However, in the following cases, relational pronouns can be used both as who and who. In general, the meaning of the expression is still different. 1. This is the baby which needs inoculation when the antecedent is baby, child, or boy. This is the baby who needs to be vaccinated.