Bob worked hard enough to pass the exam.为什么work要加ed?是否可以不加?请

Bob worked hard enough to pass the exam.为什么work要加ed?是否可以不加?请 If you work hard enough ,you'll pass the exam. you have to work hard to pass the exam.( ) ( ) you work hard you ___(not pass)the exam if you don't work hard enough. he worked enough tthat pass the exam.right or wrong? Though he worked hard,he failed to pass the ____ exam.(enter though he worked hard,( )he failed to pass the exam yet howe he studied hard,aiming at passing the exam.为什么aim要加ing?请详解. He is ( )enough to pass the exam. go to work为什么不加the She is lazy and she does not do work enough to pass the exam A good way to pass an exam is to work hard every day in the