20．Do dogs understand us？Be careful what you say around your dog．It might understand more than you think．
A border collie named Rico recognizes the names of about 200objects，say researchers in Germany．The dog also appears to be able to learn new words as easily as a 3-year-old child．Its word-learning skills are as good as those of a parrot or chimpanzee（黑猩猩）．
In one experiment，the researchers took all 200items that Rico is supposed to know and divided them into 20groups of 10objects．Then the owner told the dog to go and fetch one of the items and bring it back．In four tests，Rico got 37out of 40commands right．As the dog couldn't see anyone to get clues，the scientists believe Rico must understand the meanings of certain words．
In another experiment，the scientists took one toy that Rico had never seen before and put it in a room with seven toys whose names the dog already knew．The owner then told Rico to fetch the object，using a word the dog had never heard before．
The correct object was chosen in seven out of l0tests，suggesting that the dog had worked out the answer by process of elimination（排除法）．A month later，Rico remembered half of the new names，which is even more impressive．
Rico is thought to be smarter than the average dog．For one thing，Rico is a border collie，a breed （品種）known for its mental abilities．In addition，the 9-year-old dog has been trained to fetch toys by their names since the age of nine months．
It's hard to know if all dogs understand at least some of the words we say．Even if they do，they can't talk back．Still，it wouldn't hurt to sweet-talk your dog every now and then．You might just get a big，wet kissin return!
21．Both experiments show thatB．
A．Rico is smart enough to get all commands right
B．Rico can recognize different things including toys
C．Rico has developed the ability of learning mathematics
D．Rico won't forget the names of objects once recognizing them
22．Which of the following statements is true？B
A．The purpose of the experiments is to show the border collie's mental abilities．
B．Rico has a better memory partly because of its proper early training．
C．The border collie is world-famous for recognizing objects．
D．Rico is born to understand its owner's commands．
23．What does the writer want to tell us？C
A．To train your dog．
B．To talk to your dog．
C．To be friendly to your dog．
D．To be careful with your dog．
分析 本文是一篇科教類閱讀，主要講的是通過對一只名為Rico的博德牧羊犬進行試驗，表明它聽得懂特定話語的含義；因此作者想要告訴我們的是要對我們的狗狗友善一些，因為它們可能會給我們一個大大的吻作為回報！
解答 21-23．BBC
21題答案：B 考查細節(jié)理解，前一個試驗講的是在沒有線索的情況下Rico能夠以較高的準確率辨別主人的指令，從而取回正確的物體，表明它懂得特定話語的含義；第二個試驗是將它從未聽過名字的一個玩具和其它七個它已經知道名字的物體混在一起，主人下達指令去取不知道名字的物體時，準確率能達到70%，表明Rico能運用已經知道的物體通過排除法找到答案．以上兩個試驗表明Rico能夠辨別包括玩具在內的物體，故本題答案為B選項．
22題答案：B 考查細節(jié)理解，根據文章中的"Rico is thought to be smarter than the average dog．For one thing，Rico is a border collie，a breed （品種）known for its mental abilities．In addition，the 9-year-old dog has been trained to fetch toys by their names since the age of nine months．"（Rico被認為比一般的狗要聰明些．一方面是因為博德牧羊犬因其智力出名，另一方面是因為這只九歲的狗狗在九個月的時候就已經開始被訓練根據名字取玩具．）可知本題答案為B選項．
23題答案：C 考查寫作意圖，根據最后一段的"Still，it wouldn't hurt to sweet-talk your dog every now and then．You might just get a big，wet kissin return!"（但是，與你的狗狗進行時而不時的甜蜜交談不會有壞處，因為你有可能會得到一個大大的吻作為回報！）可知作者想要告訴我們的是"雖然狗狗不會說話，但是它們或許能明白我們的話，我們要友好地對待它們"，故本題答案為C選項．
點評 本文是一篇科教類閱讀，題目涉及多道細節(jié)理解題，做題時結合原文和題目有針對 性找出相關語句進行仔細分析，結合選項選出正確答案．推理判斷也是要在抓住關鍵句子的基礎上合理的分析才能得出正確的答案．
