什么情况下用名词复数

如图三角形ABC中,角ACB=90度,角平分线AD与高CH交与F点,DE垂直AB于E,求证:四边形CDEF是菱形. 用商不变的性质计算 化简比是应用了 （） A.商不变的性质 B.分数基本性质 C.比的基本性质? 利用商不变的性质简算560÷35 3．9÷26 2．87÷0．25=560÷（5×7） =3．9÷（ ）÷（ ）= ÷（0．25×4）=560÷7 = = = = = 符号 度 分 秒 的关系 He got up early ( ) he could catch the early bus .A.because B.so that C.when D.whetherMy young brother couldn't work out the answer and ( ).A.so could I B.nor could I C.so can I D.nor I could 如图 在rt三角形abc中 角c等于90度,沿过b点的一条直线be折叠这个三角形已知：如图，在Rt△ABC中，∠C=90°，沿过B点的一条直线BE折叠这个三角形，使C点与AB边上的一点D重合。当∠A为多少时， ( )9.Are there ____ animals ____ the farm?（A还是C?）A.many kinds … on B.a kind of … at C.several kinds of … on D.several kind of … in( ) 8.He hoped ________ doing his homework soon.（B还是D?）A.his son to finish B.to finishC.finishin 一些有趣的英语选择题1.They went to the rice fields to help the farmers ________their old clothes.A.put on B.wear C.in D.wear in 2.----No one believes what you told us yesterday.It's too surprising--------___________,that's the truth.A.Then 所有选择题答案,英语好的进 word2007中正负号和分秒符号怎么输入 word2013 插入分秒符号 用因式分解法解方程[2x-1][3x+4]=2x-1(2X-1)(3X+4)=2X-1(2X-1)(3X+4)-（2X-1)=0(2x-1)(3x+4-1)=0(2x-1)(3x+3)=0x1=1/2x2=-1第三部3x+4为什么-1 已知,如图,在Rt三角形ABC中,角ACB等于90度,CD是三角形ABC的角平分线,DE垂直BC,DF垂直AC,垂足分别为E,F,求证,四边形CEDF是正方形 1.Nobody noticed the thief slip into the house because the lights happened to ___A.be put up B.give in C.be turned on D.go out 2.The new bridge __ by the end of last month A.has been designed B.had been designed C.was designed D.would be designed3.Wh 要原因）The new shop has taken away most of my_____(custom) 1.Uncle Tom is headmaster of the school in our District.(同义句)Uncle Tom______ ______ ______of the school in or district.2.Mike wouldn't like to stay at home.Neither would Mary.Mike wouldn't like to stay at home,Mary_______,______. 要原因）1.It was a pity that you____(not attend)the meeting last Friday afternoon.2.The____(high)you climb ,the more beautiful view you will see.3.It rained heavily last night,so I didn't go out.(改为同义句)I didn't go out last night______ _ 商不变的性质是什么 商不变的性质是什么 分数的性质是商不变的性质是什么 分数的性质是什么 分数与除法的性质是什么 proper care will be ___such delicate instruments.a.taking of b.taken ofc.taken ofd.taking by.the mans said the car ___day after day by him for five years by the end of next montha.would be drivenb.would be drivingc.would have been drivend.would have 麻烦诸位1.nervous/students/tanking/very/time/an/test/a/for/be/english/can(重新排列组句子）2.I enioy___people from other countries第一题是这样的~nervous/students/Taking/very/time/an/test/a/for/be/English/can 1.when you find something,make a note ( )it is found.A.which B.at where C.in which D.where2.Great progress( )in science in the past few years.A.had been made B.will be made C.has been made D.was made3.He likes swimming( )I like skating.A.when B.while 选词填空 take up/take advantage of/take place/take a chance/take into account1 her time is fully__with writing2 we will __with the weather and go for a picnic3 we have never discovered what__between them that night4 when judging his performance,d 在三角形ABC中,角ACB=90度,角B=60度,AD CE分别是角BAC的,角BCA的平分线,AD CE相交于F 判断FE FD之间关系如果三角形ABC中 角ACB不再是直角,其他条件不变,那么前面的结论是否成立?说出理由~看不出名堂 如图所示,在rt三角形abc中,角acb等于90度,de垂直ab,ae等于be,bc等于6,ac等于10,则三角形bcd的周长是 在三角形ABC中,角ACB=90度,a.b.c分别是角A,角B,角C的对边,三角形ABC的面积是24,a+b=14,求c的长 写出十个正比例和反比例的式子,比如说正比例工作时间一定,工作效率和工作量,反比例货物的单价越低,卖出的数量就越高. 2No one tell us ____,so we neen your help.A how will we do B what should wo do C how to do it D what do 3I _____ think ____ rain this afternoon.Don't take an umbrella with you.A don't;it won't B don't;it's going to C /;it doesn't D /;it's not going t 如图,在三角形ABC中,角ABC,角ACB的平分线交于O（1）若角A=50度,求角BOC的度数；（2）设角A=n度（n为已知数）,求角BOC的度数；（3）当角A为多少度时,角BOC=3角A 如图,三角形ABC的角ABC和角ACB的平分线BE,CF相交于点G,求证: 如图,在三角形ABC中,BD,CE分别是角ABC.角ACB的平分线.（3）若角A=X度,用含X的代数式表示角BPC的度数