I doubt _______ they can complete the bridge ahead of time.
A、whetherB
这里表示的是：来的方式，要用how.
Apartfromherdevotiontoherwork，Elizabethwasalsolovedforher___(warm)andhumor.
Peopletodayarehighlyconcernedaboutthequalityoftheairthey___(breath).
Itisessentialthatyou__________anydocumentcarefullybeforesigningit.
Janeisrestless;sheis_____animportantphonecallfromherparents.
MaryacceptedDavids___(invite)tojoinhimforlunch.
