I don’t doubt ____________ she can do it well, but Idoubt _________ she is willing to do it.

Overuse of computers largelytothe failure of his eyesight，which is also a warningmessage for us all

___________inthought,healmostranintothecarinfrontofhim [ ]

Many a student ______ made that mistake before, which is another way of saying a great many students ________ made that mistake

Bill was doing a lot of physicalexercise to build up his _______.