题目内容
（请给出正确答案）
A.must be heated
B.has to be heated
C.is to be heated
D.be heated
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更多“One of the requirements for producing vapor is that the water ______ to its boiling point.”相关的问题
Although the birth rate continued to decline from its high level of the eighteenth and early nineteenth centuries the population roughly doubled every generation during the rest of the nineteenth century. As the population grew, its make up also changed. Massive waves of immigration brought new ethnic groups into the country. Geographic and social mobility — downward as well as upward — touched almost everyone. Local studies indicate that nearly three quarters of the population in the North and South, in the emerging cities — the Northeast and in the restless rural counties of the West — changed their residence each decade. As a consequence, historian David Donald has written, "Social atomization affected every segment of society," and it seemed to many people that "all the recognized values of orderly civilization were gradually being eroded.
Rapid industrialization and increased geographic mobility in the nineteenth century had special implications for women because these changes tended to magnify social distinctions. As the roles of men and women played in society became more rigidly defined, so did the roles they played in the home. In the context of extreme competitiveness and dizzying social change, the household lost many of its earlier functions and the home came to serve as a haven of tranquility and order. As the size of families decreased, the roles of husband and wife became more clearly differentiated than ever before. In the middle class especially, men participated in the productive economy while women ruled the home and served as the custodians of civility and culture. The intimacy of marriage that was common in earlier periods was rent, and a gulf that at times seemed unbridgeable was created between husbands and wives.
What does the passage mainly discuss?
A．The economic development of the United States in the eighteenth century.
B．Ways in which economic development led to social changes in the United States.
C．Population growth in the western United States.
D．The increasing availability of industrial jobs for women in the United States.
Although the birth rate continued to, decline from its high level of the eighteenth and early nineteenth centuries, the population roughly doubled every generation during the rest of the nineteenth century. As the population grew, its makeup also changed. Massive waves of immigration brought new ethnic groups into the country. Geographic and social mobility—downward as well as upward—touched almost everyone. Local studies indicate that nearly three-quarters of the population in the North and South, in the emerging cities of the Northeast, and in the restless rural counties of the West changed their residence each decade. As a consequence, historian David Donald has written, "Social atomization affected every segment of society", and it seemed to many people that "all the recognized values of orderly civilization were gradually being eroded."
Rapid industrialization and increased geographic mobility in the nineteenth century had special implications for women because these changes tended to magnify social distinctions. As the roles men and women played in society became more rigidly defined, so did the roles they played in the home. In the context of extreme competitiveness and dizzying social change, the household lost many of its earlier functions and the home came to serve as a haven of tranquility and order. As the size of families decreased, the roles of husband and wife became more clearly differentiated than ever before. In the middle class especially, men participated in the productive economy while women ruled the home and served as the custodians of civility and culture. The intimacy of marriage that was common in earlier periods was rent, and a gulf that at times seemed unbridgeable was created between husbands and wives.
What does the passage mainly discuss?______
A．The economic development of the United States in the eighteenth century
B．Ways in which economic development led to social changes in the United States
C．Population growth in the western United States
D．The increasing availability of industrial jobs for women in the Unites States
A、love
B、friendship
C、selflessness
D、all of the above
A、She was influenced by the roles she played in the films.
B、Her parents taught her to sympathize with the needy.
C、She learned to volunteer when she was a child.
D、Her family benefited from other people’s help.
ous images.
B. That is going to be the difficultpart.
C. The cut could then be treatedinstantly, so avoiding possible complications.
D. Instead of relying on hi-techhospitals, the emphasis is shifted to the home and easy-to-usegadgets.
E. Experts are also working on a"digital doctor", complete with a comforting bedside manner.
F. A toothbrush that checks blood sugaran d bacteria while your brush is currently in development in USA.
A、对
B、对
C、对
D、错
【填空题】Lesson 15 词汇拓展 Cloze-2 Fill in the blanks with the proper form of the words in the table Level Bust availability contribute relate procedural impending clarification inadequate transmission deviation obstruction Level Bust is defined as any unauthorised vertical 1 of more than 300 feet from an ATC flight clearance. Within reduced vertical separation minima airspace, this limit is reduced to 200feet. The level bust issue only 2 to aircraft in controlled airspace or a designated Air Traffic Zone outside controlled airspace and under either radar or 3 ATC control. A Level Bust can result in loss of separation between aircraft or between an aircraft and the terrain or a ground 4 such as a mast. Level busts are becoming less dangerous because improvements in technology such as better STCA (short-term conflict alert) and Mode S have improved the ability of controllers to safely manage any consequent loss of separation. Furthermore, the 5 and proper use of TCAS provides a final safety net which significantly reduces the risk of a Mid-air Collision and GPWS has also reduces the risk of a level bust resulting in CFIT( controlled flight into terrain) accident. There are a variety of factors which 6 to the risk of level bust occurring. It may be induced by controllers. For example: The ATCO is interrupted or distracted and does not take action in time to rectify an 7 loss of separation; The ATCO assigns an incorrect altitude, or reassigns a FL after the aircraft has been cleared to an altitude; The ATCO's instructions are misunderstood because of 8 English proficiency or non-use of standard phraseology. The ATCO issues a complex 9 containing more than two instructions (e.g. speed, altitude and heading). Level busts may also be caused by the pilot’s errors in which both flight crew are uncertain about ATC level instructions but failed to ask for clearance 10
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