题干

2
7
3
4
1
7
 +
1
4
 =(
2
7
1
7
 )+(
3
4
1
4
 )=
3
7
 +1= 1
3
7
 是依据()

A:加法交换律

B:加法结合律

C:加法分配律

D:加法交换律和结合律

上一题 下一题 0.0难度 选择题 更新时间:2017-09-08 10:12:33

答案(点此获取答案解析)

D

同类题1

阅读课文选段,回答后面的问题。

                                                                                                           背影
      我说道:“爸爸,你走吧。”他往车外看了看说:“我买几个橘子去。你就在此地,不要走动。”我看那边月台的栅栏外有几个卖东西的等着顾客。走到那边月台,须穿过铁道,须跳下去又爬上去。父亲是一个胖子,走过去自然要费事些。我本来要去的,他不肯,只好让他去。我看见他戴着黑布小帽,穿着黑布大马褂,深青布棉袍,蹒跚地走到铁道边,慢慢探身下去,尚不大难。可是他穿过铁道,要爬上那边月台,就不容易了。他用两手攀着上面,两脚再向上缩;他肥胖的身子向左微倾,显出努力的样子,这时我看见他的背影,我的泪很快地流下来了。我赶紧拭干了泪。怕他看见,也怕别人看见。我再向外看时,他已抱了朱红的橘子往回走了。过铁道时,他先将橘子散放在地上,自己慢慢爬下,再抱起橘子走。到这边时,我赶紧去搀他。他和我走到车上,将橘子一股脑儿放在我的皮大衣上。于是扑扑衣上的泥土,心里很轻松似的。过一会儿说:“我走了,到那边来信!”我望着他走出去。他走了几步,回头看见我,说:“进去吧,里边没人。”等他的背影混入来来往往的人里,再找不着了,我便进来坐下,我的眼泪又来了。

同类题2

完形填空

    When I was eight, I wrote my first poem. My mother read and cried, “Buddy, you didn't really write this beautiful poem!” Shyly, but1, I said yes. She poured out her 2.“It was nothing short of talent!”“What time will Father be home?” I asked. I could 3 wait to show my work to him. I spent quite some time 4 for his arrival. I wrote the poem out in my finest flourish(花体字), drew a fancy border around it and 5 I placed it right on my father's plate on the dining table. My father had begun his motion-picture career as a writer. I was sure he would be able to 6 my poem.

    At almost 7 o'clock my father burst in. He seemed 7. He circled the dining-room table, complaining about his employees. 8 he paused and glared at his plate. “What is this?” He's reaching for my poem. “Ben, Buddy has written his first poem!” my mother began. “And it's beautiful, absolutely amaze...” “If you don't mind, I'd like to decide for myself.” Father said. I 9 my head as he read that poem. It was only ten lines. But it seemed to take hours. Then I heard him dropping the poem back on the table. Now came the moment of 10. “I think it's terrible,” he said. I couldn't look up. My eyes were getting 11.

    “Ben, these are the first lines of poetry he's ever written,” my mother was saying. “He needs encouragement.” “I don't know why.” My father held his ground. “Isn't there enough 12 poetry in the world already?” I couldn't 13it another second. I ran from the dining room crying. Up in my room I 14 myself on the bed and cried the worst of the disappointment out of me.

    That may have been the end of the story, but not of its 15 for me. I realized how 16 I had been. I had a mother who said, “I think it's wonderful!” and a father who drove me to hear with “I think it's awful.” Every one of us needs that mother force, from which all creation flows; and yet the mother force alone is 17. It needs the balance of the force that 18, “Watch. Listen. Review. Improve.”

    Those 19 voices of my childhood ring in my ears through the years, like two opposing winds blowing me. 20 the two poles of confirmation and doubt, both in the name of love, I try to follow my true course.