1.Ivisitedtheschoolinwhich/whereIhadstudied;
2.Heisthemanthat/who/whom/-Iamlookingfor.
3.Ireceivedtheletterthat/which/-myuncleposted;
4.Herboyfriendisapersonwhotriestomakeherhappy;
5.Istillrememberthethingsthat/whichhappenedintheschool;
6.Themostimportantthingthatweneedtoconsideriswhowillgivethelecture;
7.AmanwhoiscalledMr.Greenwantstoseeyou.