题目

当光束通过下列分散系:①有水雾的空气 ②稀硫酸 ③蒸馏水 ④稀豆浆，能观察到丁达尔效应的是A、①②    B、②③   C、①④D、②④  答案：C解析: 用方框中所给词语的适当形式填空，使文章完整、通顺。（每词限用一次）answer, alone, oldest, start, until, fortieth,own, teach, money, laterIn Britain you are allowed to drive a car when you are seventeen. You have to get a special two—year driving license before you can 小题1:        . When you are learning, someone with a full license always has to be in the car with you because you aren't allowed to drive the car on the road 小题2:      . You don't have to go to a driving school—a friend can小题3:_       you. The person with you isn't allowed to take the小题4:_         for the lesson unless he's got a teacher's license.Before you are allowed to have a full license, you have to take a driving test. You can take a test in your 小题5:         car, but it has to be fit for the road. In the test you have to drive round for about half an hour and then 小题6:        a few questions. If you don't pass the test, you are allowed to take it again a few weeks小题7:        if you want to. In 1970 a woman passed her 小题8:          test after 212 driving lessons. When you've passed your test, you don't have to take it again, and you are allowed to go on driving as long as you like. Britain's小题9:         driver was a man who drove in 1974 at the age of 100.Before 1904 everyone was allowed to drive, even children. Then from 1904 car drivers had to have a license. But they didn't have to take a test小题10:        1935. On the early days of car driving, before 1878, cars weren't allowed to go faster than four miles an hour, and someone had to lead the car with a red flag.