化学与生活密切相关，请用相关知识回答下列问题。
（1）人体要健康地正常生长，离不开多种营养物质和多种元素发挥作用。下列食物中，能提供大量维生素的是 （填字母序号，下同）；佝偻病的发生主要是由于患者体内缺乏 元素
A．锌 B．硒 C．钙 D．氟 E.铁
（2）下列化学肥料中，加入氢氧化钙混合研磨后，能产生刺激性气味的气体有 ，属于复合肥的有 。
A．尿素 B．碳酸氢铵 C．磷矿粉 D．硫酸铵 E.硝酸钾
spread common everywhere gift think twice wheel |
43．At Christmas my uncle gave me a watch as a ．
44．My brother is an untidy worker﹣﹣﹣he leaves his tools ．
45．The soldiers the map out on the floor．
46．You should about hiring someone you've never met before．
47．Young Tan Dun liked to make music with objects like stones and papers．
False Bay is South Africa． It is one of the（1） places in the world to see a great white shark． The great white shark is known for its（2） ﹣﹣the largest sharks can grow to six meters in length and over 2,000 kilometres in weight． Great white sharks are meat﹣eaters． They catch large（3） like tuna（金枪鱼），seals（海豹）and even whales，Great white sharks also（4） boats． Simon a British researcher， was lucky to get away safely when a shark bit into his boat． About three people are killed each year（5） great white sharks．
The sharks come to hunt 60，000 seals that live in False Bay， In order to find fish， the seals have to cross the deep water of the bay﹣﹣ this is where the sharks（6） ． Great white sharks are very good hunters．They wait below the seals and then swim（7） and crash into them by surprise at 40kilometers per hour， killing （8） with one bite．
Will a shark attack something that（9） like food？
Some researchers put a carpet in the shape of a seal（10） ． At high speeds the sharks can't tell the difference．
（11） a shark choose between a plant and a fish？
When scientists put tuna and sea﹣plant in the water， the shark bites into（12） ．Even though sharks eat meat， if a plant looks like an animal， the shark attacks．
Will a shark prefer to eat a human or a fish？
When the shark has a choice between humans and tuna， it is the（13） that attracts the shark's attention． Great white sharks clearly prefer fish to humans．
These researchers show that great white sharks are（14） hunters which will attack anything that looks and acts like a fish． （15） ， that means humans can also get bitten by mistake．
（1）A． good |
B． well |
C． better |
D． best |
（2）A． colour |
B． size |
C． speed |
D． shape |
（3）A． pets |
B． insects |
C． sea﹣animals |
D． birds |
（4）A． attack |
B． protect |
C． love |
D． follow |
（5）A． for |
B． by |
C． with |
D． of |
（6）A． wait |
B． rest |
C． sleep |
D． play |
（7）A． around |
B． along |
C． down |
D． up |
（8）A． us |
B． you |
C． it |
D． them |
（9）A． looks |
B． sounds |
C． smells |
D． tastes |
（10）A． on the ground |
B． in the sky |
C． in the water |
D． in the room |
（11）A． Can |
B． May |
C． Must |
D． Should |
（12）A． all |
B． none |
C． both |
D． neither |
（13）A． human |
B． fish |
C． sea﹣plant |
D． boat |
（14）A． amazing |
B． strange |
C． kind |
D． dangerous |
（15）A． Proudly |
B． Unluckily |
C． Finally |
D． Happily |
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