问题 选择题

下列命题中错误的是

A.两组对边分别相等的四边形是平行四边形

B.对角线相等的平行四边形是矩形

C.一组邻边相等的平行四边形是菱形

D.对角线相等且互相垂直的四边形是正方形

答案

答案:D

题目分析:根据平行四边形、矩形、菱形、正方形的判定方法依次分析各选项即可作出判断.

A.两组对边分别相等的四边形是平行四边形,B.对角线相等的平行四边形是矩形,C.一组邻边相等的平行四边形是菱形,均正确,不符合题意;

D.对角线相等且互相垂直的四边形不一定是正方形,也可能是等腰梯形,故错误,本选项符合题意.

点评:本题属于基础应用题,只需学生熟练掌握平行四边形、矩形、菱形、正方形的判定方法,即可完成.

完形填空
Coin confusion
Rachel looked through troubled eyes at her sister and said, "I wouldn't have thought Eric would be a thief." Her sister Sarah replied, "Whoa, that's a      accusation to make against your best friend!"
Rachel remembered two days ago when she had brought out her coin collection for Eric to     . At the end of that day, Rachel's mother asked her to do her a favor, so she asked her friend," Is it okay if I leave you for a few minutes?" Eric said, "Go ahead. I’ll clean up here,"      at the piles of coins on the floor.
When Rachel returned, it never occurred to her to     her coins until two days later that she realized some quarters were      .
Sarah said, "Why don't you just ask him?"
"Ask him what? Hey, best friend, did you       my coin collection?" Rachel thought for a moment,        if that would be a good idea. The theft of her collection left her with a feeling of        "How could I have misjudged my friend's       ?"
The next day Rachel went to Eric's house. Eric was acting funny sort of nervous, like he couldn't be       . In fact, Rachel thought Eric acted like someone with a secret. Anger blossomed as Rachel watched Eric pretend to be kind,      Eric had obviously stolen from her. Rachel finally could not stand it anymore and stood up. Suddenly, Eric     ,"I can't stand it anymore!" Rachel was astonished at hearing her own      burst forth from her friend! Instead of sounding     , Eric sounded excited. He pulled something from underneath the chair.
"Go to open it! I was going to wait until your birthday, but I can't wait." Slowly, Rachel lifted the top of the     . Laid out in front of her were all of the quarters from her coin collection. Each quarter was in its own      in a new collection case. Each quarter shone like it was new.
Rachel felt      rush over her neck and ears. She said     , "Thank you! This means... a great deal to me." She was grateful that Eric had cut her      before she said something she would     . Eric was exactly the type of person she wanted as a friend!
小题1:
A.repeated B.falseC.baselessD.serious
小题2:
A.cleanB.storeC.chooseD.see
小题3:
A.workingB.gesturingC.playingD.glaring
小题4:
A.seekB.selectC.checkD.collect
小题5:
A.destroyed B.messedC.missingD.decreasing
小题6:
A.replaceB.stealC.pickD.remove
小题7:
A.deciding B.knowingC.askingD.minding
小题8:
A.stupidity B.abandonC.failureD.betrayal
小题9:
A.favourB.characterC.appearanceD.method
小题10:
A.stillB.confidentC.generousD.silent
小题11:
A.whenB.soC.afterD.if
小题12:
A.expressed B.condemned C.yelledD.argued
小题13:
A.purposeB.choicesC.desireD.thoughts
小题14:
A.shockedB.curiousC.guiltyD.cruel
小题15:
A.jarB.boxC.canD.bag
小题16:
A.spotB.formC.conditionD.style
小题17:
A.airB.heatC.windD.sweat
小题18:
A.absentlyB.unwillingly C.weaklyD.fearfully
小题19:
A.offB.downC.inD.up
小题20:
A.suspectB.explodeC.tolerateD.regret
填空题