[单选题]下颌第一磨牙近中接触区位于:
A. 合1/3处
B. 合1/3水平的颊1/3与中1/3交界处
C. 合1/3岁平的中1/3处
D. 中1/3处
E. 合1/3水平的中1/3与舌1/3交界处

Let children learn to judge their own work. A child learning to talk does not learn by being corrected all the time: if corrected too much, he will stop talking. He notices a thousand times a day the differences between the language he uses and the language those around him use. Bit by bit, he makes the necessary changes to make his language like other people’s. In the same way, children learning to do all the other things they learn to do without being taught — to walk, run, climb, whistle, ride a bicycle — compare their own performances with those of more skilled people, and slowly make the needed changes. But in school we never give a child a chance to find out his mistakes for himself, let alone correct them. We do it all for him. We act as if we thought that he would never notice a mistake unless it was pointed out to him, or correct it unless he was made to. Soon he becomes dependent on the teacher. Let him do it himself. Let him work out, with the help of
A. too independent
B. too critical of themselves
C. unable to think for themselves
D. unable to use basic skills

Earthquakes are something that most people fear. There are some places that have few or no earthquakes. Most places in the world, however, have them regularly. Some places, like Iran and Guatemala have them frequently. Countries that have a lot of earthquakes are usually quite mountainous.
The most talked about earthquake in the United States was in San Francisco in 1906. Over 500 people died in it. The strongest one in North America was in 1964. It happened in Alaska. Some earthquakes are not always tile ones that kill the most people. In 1755, one of the strongest earthquakes ever recorded was felt in Portugal. Around 20,000 people died.
In 1923, a very powerful earthquake hit the Tokyo-Yokohana area of Japan. A hundred and forty thousand people died. Most of them died in fires which followed the earthquake.
One of the worst earthquakes ever was in China in 1976. It killed a large number of people. The worst earthquake ever reported was also in China. 40