小博士：细心的同学们肯定发现了有些名词有单数(singular)和复数(plural)两种形式，而有些名词只有单数形式，这是怎么回事呢？让我来告诉你吧。英语中，名词按其所表示的事物的性质，可分为可数名词(countable noun)和不可数名词(uncountable noun)，可数名词有复数形式，不可数名词一般没有复数形式。名词单数变复数的变化规则见下表。

比一比，看谁写的单词多！

1　　直接加-s的单词有：________________________________.

2　　加-es的单词有：___________________________________.

3　　变y为i再加-es的单词有：__________________________.

4　　不规则变化的单词有：_______________________________.

掌握数词的用法非常重要，请你写出数字1～30，并总结规律。

(1)________　(2)________　(3)________

(4)________　(5)________　(6)________

(7)________　(8)________　(9)________

(l0)________　(11)________　(12)________

(13)________　(14)________　(15)________

(16)________　(17)________　(18)________

(19)________　(20)________　(21)________

(22)________　(23)________　(24)________

(25)________　(26)________　(27)________

(28)________　(29)________　(30)________

你总结出数词1～30有什么规律了吗？下面我们一起总结一下。

(1)从13～19都是以teen结尾，均读做/ti:n/除thirteen，fifteen外，fourteen，sixteen，seventeen，nineteen均是在four，six，seven，nine后加-teen；eighteen因eight是以“t”结尾，故直接加-een.

(2)twenty，thirty均是以-ty结尾，读做/ti／。从21～29均是在twenty后加“-”连字符，one，two，three…nine直接跟后。

Once　upon　a　time,　a　young　man　was　standing　in　the　middle　of　the　town　announcing　that　he　had　the　most　beautiful　heart　in　the　world.　A　large　crowd　gathered,　and　they　al　praised　his　heart　for　it　was　perfect.
Suddenly,　an　old　man　appeared　and　said,　“Why　,your　heart　is　not　as　beautiful　as　mine.”
The　old　man’s　heart　was　ful　of　scars（伤疤）.　Some　pieces　of　his　heart　were　removed　and　some　pieces　from　other　people　were　put　in,　but　they　didn’t　fit　quite　right.　So　there　were　several　jagged（锯齿状的）edges.　In　fact,　there　were　stil　some　holes　in　his　heart　where　the　pieces　were　missing.
The　 young　 man　 laughed,“Comparing　yours　with　mine,　mine　is　perfect　and　yours　is　a　mess.”
“Yes,”said　the　old　man.　“But,　every　scar　shows　that　I　took　out　a　piece　of　my　heart　and　gave　it　to　a　person,　and　often　he　gave　me　a　piece　of　his　heart　in　return.”
“Why　do　you　have　some　jagged　edges　in　your　heart?”asked　the　young　man.“Because　the　shapes　of　the　pieces　weren’t　the　same.”“Then　the　holes?”“Sometimes　I　gave　pieces　of　my　heart　away,　and　the　other　person　hasn’t　given　back　a　piece　of　his,　so　… but　I　don’t　care.”“How　come?”“They　remind　me　of　the　love　we　shared.”
The　young　man　was　deeply　moved.　He　walked　up　to　the　old　man,　took　a　piece　of　his　heart　out　and　gave　it　to　the　old　man.
The　old　man　placed　it　in　his　heart,　then　took　a　piece　from　his　old　scarred　heart　and　placed　it　in　the　wound（伤口）in　the　young　man’s　heart.　It　fitted,　but　not　perfectly,　as　there　were　some　jagged　edges.
The　young　man　looked　at　his　heart,　not　perfect　any　more　but　more　beautiful　than　ever.
How　sad　it　must　be　to　go　through　 life　 with　 a　 whole　untouched　heart!
【小题1】　The　young　man　stood　in　the　town　to　_____.

—Thanks ______ joining the Talk Show!

—You're welcome.

　 A. by　　　　　　 B. on　　　　　　 C. of D. for