It is required that every student___work___hard.为什么不用works,不

It is required that every student___work___hard.为什么不用works,不 It is required that every student _ a foreign language befor it is required that every citizen ,whoever he ___,___the law they required that he works all night It is required that no smoking ______ in the school. It is required that the plan__out firmlyAbe carried out Bmus it is required that the subject （ ）immediately. 为什么不用that is needed? where（does）your mother works?为什么不用is there is a possibility that it will rain.中为什么用that而不用which 和 I think it essential that...为什么不用 I think it is.. It is suggested that every citizen_____a new