如果which在从中做主语看先行词,先行词是单数谓语三单,先行词复数谓语复数,如果which修饰整个句子,一般用单数Sheisanartist,whichIamnot.她是一位艺术家,而我不是.Water,whichisaclearliquid,hasmanyuses.水是一种清澈的液体,有许多用途.Thetwopolicemenwerecompletelytrusted,whichinfacttheywere.那两个警察完全受到信任,事实上,也真是如此.②which指代主句中的形容词.如：Shewasverypatienttowardsthechildren,whichherhusbandseldomwas.她对孩子们很耐心,她丈夫却很少这样.Sheisalwayscareless,whichweshouldnotbe.她总是马虎大意,我们可不应该这样.③which指代主句中的某个从句.如：Hesaidthathehadneverseenherbefore,whichwasnottrue.他说以前从没见过她,这不是真的.④which指代整个主句.如：Inthepresenceofsomanypeoplehewaslittletense,whichwasunderstandable.在那么多人面前他有点紧张,这是可以理解的.Hemayhaveacuteappendicitis,inwhichcasehewillhavetobeoperatedon