单选题______, water is composed of two parts hydrogen and one part oxygen.

单选题According to the author, those who wanted to work as scientists ______.

单选题At that time leukemia was almost inevitably ______, but today, more than half of the people with leukemia get a cure.

单选题 How we look and how we appear to others probably worries us more when we are in our teens or early twenties than at any other time in our life. Few of us are content to accept ourselves as we are, and few are brave enough to ignore the trends of fashion. Most fashion magazines or TV advertisements try to persuade us that we should dress in a certain way or behave in a certain manner. If we do, they tell us, we will be able to meet new people with con- fidence and deal with every situation confidently and without embarrassment. Changing fashion, of course, does not apply just to dress. A barber today does not cut a boy's hair in the same way as he used to, and girls do not make up in the same way as their mothers and grandmothers did. The advertisers show us the latest fashionable styles and we are constantly under pressure to follow the fashion in case our friends think we are odd or dull. What causes fashion to change? Sometimes convenience or practical necessity or just the fancy of an influential person can establish a fashion. Take hats for example. In cold climate, early buildings were cold inside, so people wore hats indoors as well as outside. In recent times, the late President Kennedy caused a depression in the American hat industry by not wearing hats. More American men have followed his example. There is also a cyclical pattern in fashion. In the 1920s in Europe and America, short skirts became fashionable. After World War Two, they dropped to ankle length. Then they got shorter and shorter until the miniskirt was in fashion. After a few more years, skirts became longer again. Today, society is much freer and easier than it used to be. It is no longer necessary to dress like ev- eryone else. Within reason, you can dress as you like or do your hair the way you like instead of the way you should because it is the fashion. The popularity of jeans and the 'untidy' look seems to be a reaction against the increasingly expensive fashions of the top fashion houses. At the same time, appearance is still important in certain circumstances and then we must choose our clothes carefully. It would be foolish to go to an interview for a job in a law firm wearing jeans and a sweater, and it would be discourteous to visit some distinguished scholar looking as if we were going to the beach or a nightclub. However, you need never feel depressed if you don't look like the latest fashion photo. Look around you and you'll see that no one else does either.

单选题Because of the popularity of the region, visitors are advised to book hotels

单选题Our English professor is a man of French _____.

单选题When the news of his ______ with the enemy became known, he was hanged in effigy.

单选题The room was full of people and smoke. She started to feel______with the heat inside.

单选题He spoke so quickly that I didn"t ______ what he said.

单选题The farmer felt the ______ of the bad weather for years. A. effort B. effect C. efficient D. effective

单选题According to the passage, the risk of infection from airborne microorganisms would likely be greater during a ______.

单选题I would have gone to the lecture with you ______ I was so busy.

单选题This is the second time she ______ improvement on that equipment.

单选题He didn't keep on asking me the time any longer as he had had his watch ______.

单选题It can be inferred from the text that the purpose of the attack could be______.

单选题 Directions: For this part, you are allowed 30 minutes to write an essay entitled On Gratitude by commenting on the saying 'Gratitude is not only the greatest of virtues, but the parent of all others.' You should write at least 150 words but no more than 200 words.

单选题Mary ______ my letter, otherwise she would have replied before now. A. has received B. couldn't have received C. ought to have received D. shouldn't have received

单选题He wanted to read more, so he asked his friend if there was ______ to read. A. something easy enough B. something enough easy C. enough easy something D. easy enough something