介词1.介词（preposition）是用于名词、代词或相当于名词的结构之前，表示词语之间意义关系的词，介词又称前置词，它是一种虚词，不能在句中单独承担成分。2.按照词义，介词可分为表地点、表时间、表比较、表反对、表原因、表目的、表结果、表手段、表方式、表所属等。3.要求掌握的方位介词主要是in,Omnon,under,behind等。in表示在...里面，例如1.在树上inthetree/在同一个班inthesameclass/在北京inBeijing2.在世界上intheworld/在河里intheriver/在城市inacity3.在阳光下inthesun/在北方inthenorth/inChina在中国4.在第五中学inNo.5MiddleSchool5.在……的前部inthefrontof在……前面infrontof6.在……中间/（内部）角落inthemiddle/cornerof7.固定用法：住院inhospital/在露天intheopenair/躺着看书readinbed8.站成行standinline/处于危险中indanger/处于麻烦中introuble/惊奇地insurprise9.用英语inEnglish/穿红色的inred/以…方式in…wayofunder意为在……下面，可以用在抽象名词之前，例如1.underthetree在树下2.underthedesk在桌子底下3.underthepressure在压力下Myshoesareunderthebed.我的鞋子在床底下。Hisbikeisunderthetree.他的自行车在树底下。on表示在…上面，例如1.在墙上onthewall/在…的另一边ontheothersideof/在左边/右边ontheleft/right2.在左/有手边ontheleft/righthandside/在火车上onthetrain3.在电视/收音机/电话/网上onTV/theradio/thetelephone/theInternet4.固定用法：访问…onavisitto…/展览onshow5.在去…的路上onthewayto…6.onmyhead/nose表示附着在表面上，覆盖等，表示接触的面上、边上、线上，用on。Therearemanyapplesonthetree.Therearemanybirdsinthetree.inthetreeonthetreeTheboyisinthetree.TheappleisonthetreeinonunderWhereisTom?1.Iputmybooks____mybag.2.Therearesomeapples___thetree.3.Look,whoisthegirl___thetree?4.Ourclassroomis___thetallbuilding.5.Thechairis_____thedesk.1.Iputmybooks__in__mybag.2.Therearesomeapples_on__thetree.3.Look,whoisthegirl_in__thetree?4.Ourclassroomis_in__thetallbuilding.5.Thechairis_under____thedesk.1.in（在……里面）2.on（在……表面之上）3.under（表示在……之下）GoodbyeClass!
