九年级英语Unit4 情态动词 课件仁爱版.ppt

情态动词 情态动词 一 情态动词的含义 情态动词表示说话人对某一动作或状态的的态度 认为 可能 应当 必要 等 情态动词不能单独作谓语 必须和不带to的动词不定式连用 情态动词没有人称和数的变化 二 几种主要的情态动词 1 表示可能的情态动词 may might could can must 1 may might could都可以用来表示可能性 意思是 可能 也许 它既表示现在的可能性 也表示将来的可能性theymaybewaitingatthestation you dbettertakeanumbrella itmightraintonight thephoneisringing itcouldbetim ihaven tdecidedwheretospendmyholidays imaygotoireland thebusdoesn talwayscomeontime wemighthavetowaitafewminutes 它们的否定形式是 maynot mightnot意思是 可能不 i mnotsurewhethericanlendyouanymoney imaynothaveenoughmoney itmightnotbetrue annmaynotcometothepartytonight sheisn twell 2 may might could后面接havedone的形式 表示一种过去的可能性 是对过去动作的推测 hemayhaveleftyesterday iwonderwhyhewasinsuchabadmoodyesterday hemaynothavebeenfeelingwell hemighthaveknownaboutit tomcouldhavetakenit hewasherealongyesterday 3 must也表示比较有把握的推测 是有一定事实基础之上的判断 thepolicearestoppingallcars theymustbelookingfortheescapedprisoner thelightison theymustbeathome youhavebeentravelingallday youmustbeverytired 4 can一般用在否定和疑问句中表示可能性 youhavejusthadlunch youcan tbehungryalready theyhaven tlivedhereforverylong theycan tknowmanypeople thatcouldn tbejohn iknowhe sstilloutoftown thereissomeoneoutside whocanitbe canhestillbealiveafteralltheseyears 5 must can t couldn t后面可以接havedone表示对过去的判断 thephonerangbutididn thearit imusthavebeenasleep janewalkedpastmewithoutspeaking shecan thaveseenme youcouldn thaveforgottenmyname 1 therestaurant beverygood it salwaysfullofpeople 2 therestaurant beverygood it salwaysempty 3 whereisbob i mnotsure he behavinglunch 4 tedwasn tatworklastweek he be ill 5 ileftmybikeoutsidethehouselastnightandthismorningitisn tthereanymore somebody take it 6 itrainedeverydayduringtheirholiday sothey have averynicetime 7 iwassurprisedthatsarahwasn tatthemeeting she know aboutit 8 iwonderwhykaydidn tanswerthephone she be asleep 答案 1 must2 can