设A为n个元素的集合，则A上有()个二元关系。

Heavy rains ____the river.(rise raise)请问选哪一个?为什么? Jane has three ping-pong balls对三个乒乓球画线提问 选择并抄写正确的单词.After the heavy rain,the river _____ （rose,raised） 7cm. She has some ping-pong balls.（改为否定句） Was.because of the heavy rain that the river floodedA.thisB.itC.thatD.one空格在Was和because之间 ①Tony has three ping-pong balls .(对three oing-pong balls提问) ___ ___ Tony ___?②Volleyball is difficult for me.(对difficule提问) ___ ___ volleyball for you?③Let's play soccer after class.(改为同义句） ___ ___ ___ soccer after class The river is .(rise) after the rain .So we can't swim in it. what are you going to do with the exchange students?分为at school 和after schooi来答 一个说15个就行. When are you going to do with the exchange students?（At school or after school） Whayt are you going to do with the exchange students?（可以从课内和课外两方面来回答） Some famous__(科学家)will come to visit our school next Friday 连词成句 going,the,you,do,with,to,what,are,flowers Word had come ____some American guests will come for a visit to our college next week.A what B that C whether D when going,the,you ,do,with,to,what,are,flowers怎样排序 it’s _ that some foreignstudents will come to our school next weekA.sure B.right C.real D.true ( )Some foreigners_______our school yesterday morning.A,visit B,will visit C,visited D,have visi)Some foreigners_______our school yesterday morning.A,visit B,will visit C,visited D,have visited Does your brother play ping-pong __________? 时态填空it__(begin) to rain when i __(sit) on the bench an hour ago. Does he have a ping-pong ball?中文意思 when is the rain 什么在come make throw中选 How _____ ping-pong balls does he have? ( ) We were walking along the river _____ it suddenly began to rain.A.as B.while C.when D.then It's a long time since i saw you last 这句中的it是不是形式主语?那有没有真正主语？这句句子里有没有真正主语？是什么? The meeting _________ tomorrow will be of great impqrtance .All ofus should attend it.Aheld B to be held Cbeing held Dis going to be held The water in the river is ----higher and higher because of the heavy rain.A raising Blifting Cput up Drising 各位高手帮帮忙、选哪一个啊、纠结ing —Long time no see. _Oh,it like years since I last saw you. A.looks B.seems C.feels D.sounds应该选择B还是C，为什么 After the rain ,the water in the river rose several meters.这里为什么用rose 而不用be+过去分词拜 Long time no see!Oh it(seems)like years since I last saw 为什么不用looks Long time no see!Oh it(seems)like years since I last saw 为什么不用feels After the rain ,the water in the river _____ seAfter the rain ,the water in the river _____ several meters.A.was risen.B.rose.C.raisedD.was raised long time no see!---oh,it____like yearssince i last saw you.A feels Bsounds Cseems DlooksA和C哪个对?我认为seem like是似乎好像的意思 ,而 feel like也是固定搭配,后面也可以加名词,表示似乎好像啊,所以,到底答案是 There will be a meeting tomorrow.(改为一般疑问句作否定回答） ——------ ------be a meeting tomorrow