如图所示,一个综合实践小组用一段漆包线绕成线圈 ,用小刀刮两端引线的漆皮,一端全部刮去,另一端只刮上半圈或下半圈。将线圈
放在用硬金属丝做成的支架 m 、 n 上,并按图示连接电路,则电磁铁的上端是 ______ 极。闭合开关,用手轻推一下线圈,线圈会持续转动,这就是简易的 ______ (填 “发电机”或“电动机”)。
我国具有完全自主知识产权的百万千瓦级核电技术电站—“华龙一号”首堆年底即将投产。核燃料在核反应堆中发生的是______(填“裂变”或“聚变”),核能是______(填“可再生”或“不可再生”)能源。
长江被誉为“黄金水道”,是因为长江( )
A.径流量大 B.航运价值大 C.水力资源丰富 D.矿产资源丰富
我国东北地区的城市集中在交通干线沿线地区,特别是哈大线,滨洲线,滨绥线沿线地区. _______(判断对错)
请根据相关名著内容填空。
古今中外名著里留下很多师徒佳话。《西游记》中,孙悟空因______事而与唐僧结下师徒情缘,一心护送师傅西天取经;《简爱》中,因至爱之师谭波尔的离开,简爱也离开洛伍德学校到______当家庭老师;《红星照耀中国》中,毛泽东的中学老师______,五十岁时来到苏区任教育部长,开展真正的革命教育。
Animals are our friends. Sometimes they make trouble, but sometimes they can help us. And they hope to live a happy life, too. Here are two real stories from our readers.
The first story is from Ray. "My cat, Tiger, hates it when I use my iPad because it takes my attention away from him. One year, I had a fall at home and was on the floor for 16 hours. During this time, I was unable to move and couldn't get to the phone to call for help. Tiger stayed by my side until he disappeared under my bed. 'What's he pup to?' I wondered. To my surprise, he started to push something towards me. It was my iPad, which I didn't realize had fallen off the bed and onto the floor. He probably didn't know what it was, but he knew that it made me happy. Thanks to Tiger, I was able to communicate with my friend, Becky, who then told my doctor. "
The second story is from Colin. "Years ago, my friend Julius saved a bird—a wild 'Mom' cockatoo(鹦鹉)from the side of the road and kept it as a pet in a big cage(笼子). It lost one of her wings, so she was unable to return to the wild. Soon, two wild cockatoos came visiting and one 'Dad' bird wanted to find his way into the cage. The 'Mom' cockatoo in the cage was soon expecting. But as she couldn't fly, 'Dad' cockatoo built a home in the tree, keeping off everyone who got close to 'Mom' cockatoo. 'Baby' cockatoo would spend his days flying off with his dad, leaving his mom behind. She would sit and wait until they returned home each afternoon. The family stayed together happily. "
After reading the stories, don’t you think we should get along well with animals? No matter they are our pets or live in the wild, they have their feelings. We should respect every life in the world.
46. ____________ is the owner of the cat.
A. Becky B. Julius C. Colin D. Ray
47. The underlined word "it" in Paragraph 2 refers to the_____________.
A. phone B. cat C. iPad D. bed
48. "Mon" cockatoo didn't return to the wild because ____________________.
A Julius caught it as a pet B. she vas badly hurt and couldn't fly
C. she preferred the life in the cage D. "Dad" cockatoo built a home in the tree
49. The main idea of the passage is that _____________.
A. Ray, Becky and Colin are animal lovers B. we shouldn't use iPad too much
C. friends should help each other D. we should respect every life in the world
50. In which part of a newspaper would you probably read the passage?
A. Sports news. B. People and animals. C. Health. D. Travel.
完成下列图的反射光路图。
资本主义经济的发展,需要大量自由却 “ 一无所有 ” 的农民,要求建立广阔、统一的国内市场,而当时的封建政权却是建立在自给自足、分散的小农经济基础之上。这意味着( )
① 推翻封建政权才能为资本主义发展扫清障碍
② 资本主义生产关系的确立需要大量劳动力
③ 资本主义的发展需要大量货币资本
④ 资本主义制度代替封建制度是一个长期过程
A . ①② B . ①④ C . ②③ D . ③④
如图描述的情景发生在( )
A.17世纪的俄国 B.18世纪的法国
C.19世纪的德国 D.20世纪的美国
如图,在平面直角坐标系中,直线 分别与 x 轴、 y 轴交于点 B 、 C ,且与直线
交于点 A .
( 1 )求出点 A 的坐标;
( 2 )若 D 是线段 OA 上的点,且 的面积为 12 ,求直线
的解析式;
( 3 )在( 2 )的条件下,设 P 是射线 上的点,在平面内是否存在点 Q ,使以 O 、 C 、 P 、 Q 为顶点的四边形是菱形?若存在,直接写出点 P 的坐标;若不存在,请说明理由.
2021年1月20日,美国当选总统、民主党人________在首都华盛顿宣誓就任美国第46任总统。( )
A . 特朗普 B . 拜登 C . 哈里斯 D . 奥巴马
“大兴安岭,雪花飘飘;长江两岸,柳树发芽;海南岛上,鲜花盛开。”这是对王先生在外出差一周时间内拍下的三张景观照片的描写。景观差异如此之大的原因是( )
A.我国跨经度广
B.我国跨纬度广
C.我国地形复杂
D.距海远近不同
“自己才是自己的镜子”,人必须学会认识自己,这是因为
①人们必须要学会正视自己,实事求是,全面客观地看待自己 ②正确认识自己,才能明己之长,知己之短,确定符合自己实际情况的目标 ③正确认识自己,才能挖掘自身的潜能,不断提高自身素质 ④正确认识自己,获得更大的自我发展空间,从而塑造一个崭新的自我
A. ①②③ B. ①②④ C. ①②③④ D. ②③④