定语从句中不用that的情况

不用that的情况：a)在引导非限定性定语从句时(错)Thetree,thatisfourhundredyearsold,isveryfamoushere.b)介词后不能用Wedependonthelandfromwhichwegetourfood.c)多用who的情况①关系代词在从句中做主语Afriendwhohelpsyouintimeofneedisarealfriend.②先行词为those,people时Thosewhowereeitherfoolsorunfitfortheirofficescouldnotseethecloth.③先行词为all,anyone,ones,one指人时Onewhodoesn'tworkhardwillneversucceedinhiswork.④在Therebe句型中Thereisastrangerwhowantstoseeyou.⑤在被分隔的定语从句中AnewteacherwillcometomorrowwhowillteachyouGerman.⑥在有两个定语从句的句子中，其一用who，其二用that,但若先行词后接两个以上的并列定语从句时，后一个必须重复前一个关系代词。Thestudentwhowaspraisedatthemeetingisthemonitorthatisverymodestandstudiesveryhard.Thereisateacherwhoisalwaysreadytohelpothersandwhoenjoyswhathedoes.