题目内容
20．Over 1，500 languages are spoken in the world．分析 世界上有1500多种语言在被说．
解答 答案：spoken．
首先结合首字母s根据语境推测句意是"世界上有1500多种语言在被说．"，句子表述的是一般性的事实，所以用一般现在时，主语 languages 是动作 speak的承受者，所以用被动语态，一般现在时被动语态的构成是：主语+am/is/are+动词的过去分词，所以答案是：spoken
点评 做这类题型，首先根据所给单词首字母明确句子所要考查的单词的拼写，再结合相关语法知识对单词做出形式上的变化．
练习册系列答案
相关题目
8．Man has invented four kinds of satellites （卫星）．The first kind of satellite studies the （31）D of the earth．They are used to make maps．They also help countries to see where they may （32）Boil or gold．
The second kind of satellite is used to guide ships and planes．A ship or a plane can （33）B a message to the satellite，and the satellite can find out （34）A the ship or the plane is．
The third kind studies the weather．These satellites （35）Bclouds and strong winds moving across the earth．They warn countries to make preparations （准备） when very （36）Dweather is coming．（37）A kind is used for communication．Telephone calls （38）C countries can be sent by these satellites．Some can carry hundreds of calls at the same time．The call is sent to the satellite，then the （39）Dsends it to a station in the country and this country is being phoned．These satellites also carry pictures； they can receive and send about eight （40）B at a time．
The second kind of satellite is used to guide ships and planes．A ship or a plane can （33）B a message to the satellite，and the satellite can find out （34）A the ship or the plane is．
The third kind studies the weather．These satellites （35）Bclouds and strong winds moving across the earth．They warn countries to make preparations （准备） when very （36）Dweather is coming．（37）A kind is used for communication．Telephone calls （38）C countries can be sent by these satellites．Some can carry hundreds of calls at the same time．The call is sent to the satellite，then the （39）Dsends it to a station in the country and this country is being phoned．These satellites also carry pictures； they can receive and send about eight （40）B at a time．
| 31．A．biology | B．history | C．physics | D．geography |
| 32．A．study | B．find | C．carry | D．choose |
| 33．A．write | B．send | C．take | D．bring |
| 34．A．where | B．which | C．what | D．that |
| 35．A．search | B．watch | C．notice | D．see |
| 36．A．sunny | B．cool | C．fine | D．bad |
| 37．A．The last | B．Another | C．One | D．Any other |
| 38．A．during | B．along | C．between | D．of |
| 39．A．TV | B．telegraph | C．telephone | D．satellite |
| 40．A．plays | B．programs | C．films | D．object |
15．Something necessary to prevent the serious air pollution．（ ）
| A． | must do | B． | must be done | C． | may do | D． | may be done |
5．I saw some pancakes in the plate，but now there is left in it．（ ）
| A． | none | B． | something | C． | nothing | D． | no one |
10．There are two educations．_____ should teach us how to make a living and how to live．（ ）
| A． | One； another | B． | Some； others | C． | One； any other | D． | One； the other |