题目内容
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Only after they had performed hundreds of experiments did they succeed in (solve) ______the problem.
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更多“Only after they had performed …”相关的问题
Only after he had finished watching the football game ____________ (他才开始写报告).
A．freemen had incentives to produce more.
B．masters had greater incentive to make their workers harder.
C．slaves never starved, no matter what they produced.
D．productivity could go in only one direction.
A．Because she hadn't heard of the writer at the time.
B．Because it wasn't on any of the professors' reading lists.
C．Because it was published after she had finished her research.
D．Because it was only available in French.
查看材料
What is the title of this work？
听力原文： As my train was not due to leave for another hour, I had plenty of time to spare. After buying some newspapers to read on the journey, I made my way to the luggage office to collect my suitcase I had left there three days before. There were only a few people waiting. I took out my wallet to find the receipt for my case. Unfortunately, it was nowhere to be found.
When my turn came, I explained the situation sorrowfully to the assistant. He then handed me a form. and told me to make a list of the chief contents of the case. Only when they were correct could I take the case away. I racked my brain trying to remember all the articles I had packed in a hurry. After I had filled out the form, I went to look among the shelves. There were hundreds of cases and for one dreadful moment I began to worry that someone might have already claimed my case. To my great relief, the case was lying on its side high up in a corner. After I had examined the items inside, the assistant told me to take the case away. Again I took out my wallet: this time to pay. I pulled out a ten-shilling note and the "lost" receipt flipped out with it. Blushing, I looked up at the assistant. He was nodding his head knowingly, as if to say that he had often seen this happen.
(23)
A．A Trip by Train.
B．The "Lost" Receipt.
C．An Embarrassing Moment.
D．At the Luggage Office.
Questions 26 to 28 are based on the conversation you have just heard.
26.
A. They shared mutual friends in school.
B. They had known each other since childhood.
C. They shared many extracurricular activities.
D. They had many interests in common.
听力原文： Battle after battle, the Americans suffered heavy loss. General Washington led his forces across the Hudson River.' The British close behind, driving Washington further south to the Delaware River. Washington succeeded in getting all his men safely across just before the British troops reached the river.
The British had at least 35,000 troops in their camps, while Washington had only 3,000 fighting men left by this time. Men were leaving the American Army daily. Quite a few of them had left to take care of their farms and families. Others had gone away because they were old and hungry. Nobody could hold these men back. Things began to look black indeed for the revolutionaries. It was at this moment that Tom Paine, then an ordinary soldier in the American camp ,wrote the words, "There are times that try men's souls."
(34)
A．The Canadian River.
B．The Hudson River.
C．The Mississippi River.
D．The Amazon River.
The writer went to tile next town by taxi.
A．True.
B．False.
听力原文： In the old days, fresh food had to be eaten in the city no more than one or two days after it left the farm. If kept longer, it would spoil. One of the reasons behind it is that the air contains many living things that can harm our food. Some things, such as insects, can be seen by us. Others, like bacteria, can be seen only with a microscope.
All living things need water and man discovered that if this water is removed, the activity of the bacteria which causes food to go bad is prevented. In other words, we can protect some of our food by drying it. Besides, living things can only grow at certain temperatures, so we can also protect our food by heating or cooling it.
A New York man had an idea. He filled a wooden railroad car with tons of butter. The car was hooked to a train and pulled from New York to Boston. How could this be done？ The butter was packed in ice, and twice during the trip more ice was added. This was the first refrigerator ear. As a matter of fact, People also used wooden boxes filled with ice to keep their food. Now we have mechanical refrigerator cars and mechanical refrigerators at home and stores and other places that need them.
(33)
A．Food had to be kept in the ice box.
B．Fresh food must be eaten within one or two days after being shipped from the fame.
C．Food must be delivered from the farm within one or two days.
D．Food must be kept in the places near the farm.
