培优专项训练(四)Ⅰ.单项填空()1.You________wearsportsshoeswhenyouclimbamountain.A．can'tB．shouldn'tC．mustn'tD.haveto()2.—Haveyoudecidedwheretogoforyoursummervacation?—Notyet.We________gotoQingdao.Itisagoodplaceforvacation.A．mayB．shouldC．needD．must()3.Thetalentedboy________writelyricswhenhewasattheageoften.A．mayB．couldC．mustD．should()4.Theworkistoohardforhim.He________finishitontime.A．can'tB．mustn'tC．shouldn'tD．needn't()5....