it is essential that all these features be checked twice.这句话对吗?这句话语法对吗?总觉得be checked 很别扭!

The essential features of something are those features that make it the thing that it is. I think it essential that...为什么不用 I think it is.. It is absolutely essential that 怎么看出是虚拟语气啊 It is essential that you ____on time.A.be B.are C .were D.being It is essential that everyone ___ what to do.A.knowB.knows为什么不是B呢? 64.你务必参加这个会议.（It is essential that…） AT shcool,it is essential that every child--equally regardless of family backgroundAtreatingBtreatedCbe treated Dis treated It is only with the heart that one can see rightly； what is essential is invisible to the eye. it's only with the heart that one can see rightly,what is essential is invisible to the eye It is essential that these application forms _____A.must be sentB.will be sentC.are sentD.be sent It is essential that the human does not make a mistake这句话是什么从句,是什么时态的啊? It is essential that the program _________ into the computerA：load B：be loaded C：will load D：loads it is essential that computer security professionals should（ ）in the design of（ ）（ ）and（） what is essential is not that his policy works,but that the public believe that it is.From him to be reelected,what is essential is not that his policy works,but that the public believe that it does.这句话的后半句but that the public believe th What's the diffents of these two sentences?1.It is essential to follow the .2.It is essetial that you follow the. 此句中的it is that是什么句型,英语达人请进!Certain it is that all essential processes of plant growth and development occur in water.此句中的it is that是什么句型? 有It is essential for sb to do吗 This is a very difficult operation.It is essential that you ________ for emergencyA.are to be prepared B.would preparedC.be prepared D.must be prepared