Do Animals Dream?

You can’t see your sleeping pet’s brain waves, but its behavior can tell you when Fido or Fluffy might be dreaming. If you watch closely, you’ll see that as your cat falls asleep, her breathing becomes slow and regular and her body still. She has entered the first stage of sleep, (21) ______ (call) slow-wave sleep. After about 15 minutes you’ll notice a change (22) ______ her eyes move under her closed lids. Fluffy has entered the REM(Rapid Eye Movement), or dreaming, stage of sleep. Although she moves and makes little grunting noises, messages from her brain to the large muscles in her legs (23) ______ (block), so she can’t run about.

Back in 1963, Michel Jouvet, a French scientist who was studying sleep in cats, (24) ______ (interrupt) their sleep paralysis, the state of being unable to act or function properly. (25) ______ ______ they were completely asleep, the dreaming cats began to chase balls that Jouvet couldn’t see and bent their backs at invisible enemies. He figures he was watching them act out their dreams!

What were they dreaming about? Mostly, the dreaming cats seemed (26) ______ (practise) important cat skills: stalking, pouncing, and fighting.

In (27) ______ study, Matt Wilson, a neuroscientist, recorded rats’ brain waves while they learned mazes(迷宮). One day, he left the brain-wave-recording machine on while the rats fell asleep. The pattern of brain waves in the sleeping rats matched the pattern from the maze so closely that Wilson could locate exactly which part of the maze each rat was dreaming about!

Many researchers now think that in both people and animals, one purpose of dreams is to practise important skills and nail down recent learning. This may explain why so many people dream about fighting and escaping, skills (28) ______ were probably vitally important to our ancestors, and why dreaming affects our ability to learn.

Do all animals dream? From looking at the brain waves of sleeping animals, scientists think that all mammals dream, such as humans, dogs, lions, and whales, but fish (29) ______ not. (They’re not sure about birds.)

How often animals dream seems to be tied to body size. Cats dream about every 15 minutes, mice every 9 minutes, and elephants every 2 hours. And though cows and horses usually sleep standing up, they only dream when (30) ______ (lie) down.

答案：

21. called? ??? 22. that? ?????? 23. are blocked?? 24. interrupted? 25. Even though/Even if

26. to be practising? 27. another?? 28. that/which?? 29. do?? 30. lying?

解析：

21. called

這里隱藏了一個(gè)非限制性定語(yǔ)從句來(lái)修飾第一階段的睡眠，點(diǎn)出了這個(gè)階段睡眠的名字。Call 與第一階段的睡眠呈被動(dòng)關(guān)系，所以變形為called。 She has entered the first stage of sleep, （which is）called slow-wave sleep.

22. that

同位語(yǔ)從句。her eyes move under her closed lids 解釋抽象名詞change。

23. are blocked

messages from her brain 與block 呈被動(dòng)關(guān)系，同時(shí)前面句子時(shí)態(tài)為一般現(xiàn)在時(shí)，所以應(yīng)是are blocked。

24. interrupted

Back in 1963,（時(shí)間狀語(yǔ)） Michel Jouvet, a French scientist who was studying sleep in cats,（插入語(yǔ)可省略）________（interrupt） their sleep paralysis, the state of being unable to act or function properly.（同位語(yǔ) 解釋sleep paralysis）所以主句為 Back in 1963, Michel Jouvet ________（interrupt）their sleep paralysis. 句子缺少動(dòng)詞，所以不可以填現(xiàn)在分詞，同時(shí)注意時(shí)間狀語(yǔ)，應(yīng)填過(guò)去式。

25. Even though/Even if

they were completely asleep, 與the dreaming cats began to chase balls that Jouvet couldn’t see and bent their backs at invisible enemies 呈轉(zhuǎn)折讓步關(guān)系，同時(shí)這里為兩個(gè)空。

26. to be practicing

固定搭配，sb. seem to do sth. 同時(shí)前文What were they dreaming about? 與后文stalking, pouncing, and fighting 提示這里應(yīng)用現(xiàn)在進(jìn)行時(shí)來(lái)表示這個(gè)dream的過(guò)程。

27. another

前面時(shí)Michel Jouvet 的研究?jī)?nèi)容，后一段轉(zhuǎn)變?yōu)镸att Wilson 的研究?jī)?nèi)容。

28. that/which

限制性定語(yǔ)從句，were probably vitally important to our ancestors修飾skills。后半句缺少主語(yǔ)，同時(shí)skills為物，先行詞填that /which。

29. do

填助動(dòng)詞表示強(qiáng)調(diào)作用，完整句子為 fish do not dream，與前文許多做夢(mèng)的動(dòng)物形成反差，fish單復(fù)數(shù)同形，這里表復(fù)數(shù)，所有的種類的魚(yú)。

30. lying?

時(shí)間狀語(yǔ)從句，點(diǎn)出牛和馬只在他們躺下的時(shí)候做夢(mèng)，cows and horses與lie（躺下）呈主動(dòng)關(guān)系，用lying表示狀態(tài)。完整句為 they only dream when （they are） lying down, 可以同時(shí)省略主語(yǔ)和謂語(yǔ)。