液压泵油箱里的油液绝对压力必须是（）大气压力。 A.＜ B.＞ C.≤ D.≥ 发布时间：2018-01-27 21:48 │ 来源：www.tikuol.com 题型：单项选择题 问题： 液压泵油箱里的油液绝对压力必须是（）大气压力。A.＜B.＞C.≤D.≥
题型：单项选择题 阅读理解。 Have you ever noticed an advertisement which says "Learn a foreign language in six weeks, or yourmoney back! From the first day your pronunciation will be excellent. Just send…" and so on? Of course, it never happens quite like that. The only language that is easy to learn is the mother tongue. And think how much practice that gets! Before the Second World War people usually learned a foreign language in order to read the literature (文学) of the country. Now speaking the foreign language is what most peoplewant. Every year many millions of people start learning one. How do they do it? Some people try at home,with books and tapes; some use radio or television programmes; others go to evening classes. If they usethe language only two or three times a week, learning it will take a long time, like language learning at school.A few people try to learn a language fast by studying for six or more hours a day. It is clearly easier to learnthe language in the country where it is spoken. However, most people cannot afford this, and for many it isnot necessary. They need the language in order to do their work better. For example, scientists and doctorsmainly need to be able to read books and reports in the foreign language. Whether the language is learnedquickly or slowly, it is hard work. Machines and good books will help, but they cannot do the students workfor him. 1. In the advertisement it is possible for a person to learn a foreign language ______. [ ]A. more than two month B. half a year C. six months D. less than two month 2. Before the Second World War people learned a foreign language in order to ______. [ ]A. speak to each other B. listen to the radio C. read something they didn't know D. write the literature of the other country 3. The easiest way for us to learn a foreign language is ______.[ ]A. using the language six or more hours a dayB. learning the language at school C. studying the language in the foreign countryD. reading the foreign stories as many as possible 4. Most people now learn a foreign language to ______.[ ]A. read books and reports in a foreign languageB. talk to foreign friendsC. go to the other country to learn a language wellD. try their best to work better 5. The passage tells us that ______.[ ]A. the more you spend, the quicker you'll learn the language B. it is possible for you to learn a foreign language in six weeksC. it is not good for you to learn a foreign language by yourself D. the quicker you learn a foreign language, the more you must pay for it 查看答案
题型：单项选择题 一列火车做匀变速直线运动，一人在轨道旁观察火车的运动，发现在相邻的两个10s内，列车从他跟前分别驶过8节和6节车厢，每节车厢长8m（连接处长度不计）．求：（1）火车的加速度a（2）此人开始观察时火车速度的大小． 查看答案
题型：单项选择题 Due to the widespread ______ of this medical technology, more diseases can be discovered and treated at an early stage.A．presentation B．appreciationC．qualificationD．application 查看答案