题目

已知R2+离子核外有a个电子，b个中子。表示R原子符号正确的是（    ） A．         B．         C．         D． 答案：C  (A) He who has never been to the Great Wall is not a true man. The US president Barack Obaraa is a true man.Obama had a four-day visit to China from 15th to 18th November, 2009. He had a very busy sched- ule(日程) . But he still spent some time (B)       (visit) the Forbidden City and the Great Wall.  When a leader visits another country,he or she sometimes goes to the country's most famous places. It is to show the respect for the local cul?ture. For the leaders,it's also a good time to relax during a tiring foreign trip.  Obama spent 50 minutes in the Forbidden City on the afternoon of 17th November. He thinks the Forbidden City is a wonderful place to visit. He said, "111 come back with my girls and my wife.”  On 18th November,he paid a quick visit to the Great Wall at Badaling. There,he enjoyed a mo?ment of peace. (C) He had a good time there.  "It's magical. It reminds you of the course of history," Obama said about the Great Wall. 根据短文内容，完成下列各题。1.将(A) 处句子译成汉语。2.写出(B) 处所给词的正确形式。3.How long did Obama stay in China?4.What does Obama think of the Forbidden City?5.写出(C) 处句子的同义句。