he isn't at school.i think he ------be ill A.has to B.shall C.can D.have to

He isn't at school .I think he ( )be ill.can,shall,must,has to ,原因. he isn't at school i think he -----be illAcan Bshall Cmust Dhas to 选哪个 he isn't at school.i think he ------be ill A.has to B.shall C.can D.have to Bob____at school.He is at home.【can't,isn't,aren't,don't,doesn't】 Tony isn't at school because he is ill.Tony isn't ________ school _______ ______ illness. He is ( )home.He isn't( )school. He isn't at school today because he coughs _(terrible) these days li lei isn't at home.maybe he is at school.=li lei is _ at home_at school -Tom isn't at school today.He ____ ill at home. -I'm not sure,let me call him. A may be B must be He isn't at school today.I think he _____be willA.canB.shallC.mustD.should选哪个?为什么?不好意思,是be ill 对划线部分提问He isn't at school because he is ill.—— —— he at school.He isn't at school __because he is ill___ He isn't in the school .I think he __be ill.A.can B.must为什么? He has many friends at school,___?A has heB does heC doesn't heD isn't he为什么 He can't be at school,___?A.is he B.isn't he C.can he D.can't he He can't be at school, ____ ? A.is he B. isn't he C.can he D.can't he 选哪个?为什么? .He can't be at school,____ A.is he B.isn't he C.can he D.can't he请帮忙解释为什么选A. 改错:I afraid he isn't at home at the moment I don't think he can （ ）at school.