They all have blond hair and “strange eyes.” 24 the children grow, they run around the village in a pack, wearing identical clothing and hairstyles, staring at everyone impolitely. 25 one child learns is also known by the others instantly.
答案：(D) What
What 引導名詞子句作句子主詞，「一個孩子學到的東西」；Which（哪一個）、While（當……同時）、Where（哪裡）都不能這樣構成名詞子句主詞。
空格在整句的最前面，你會直覺把它當成疑問詞在問問題，於是 Which（哪一個）與 What（什麼）看起來都可以。但這一句不是問句，它是一個直述句，空格帶出來的整串是這個句子的主詞。答對率四成四，卡在沒有先把整句的結構看清楚。
四個選項都是 wh- 詞，先數成分。空格後面是 one child learns，主詞是 one child、動詞是 learns，而 learn 是及物動詞，這裡卻看不到受詞——這個洞就是關鍵。再往後看，is also known by the others instantly 才是整句的主要動詞部分，所以空格帶出來的那一整串要當這個句子的主詞。需要一個字同時做兩件事：自己就是一個名詞（整串才能當主詞用），又要能填進 learns 後面那個受詞的洞。這正是複合關係代名詞 what，意思等於 the thing(s) that（劍橋 English Grammar Today 的 what 條目）。還原一次就通了：The thing that one child learns is also known by the others instantly.（一個孩子學到的東西，其他孩子立刻也都知道。）。這一題的鑑別度 62，分開的就是有沒有發現 learns 後面缺了受詞。這一格與 93 年第 18 題正好是一體兩面：那一題的子句成分已經滿了，what 沒有位置可站，所以填 that；本題的子句缺了受詞，非 what 不可。全庫同判準的還有 92 年第 27 題、95 年第 24 題、100 年第 29 題、107 年第 26 題，都是「子句缺一個成分，由 what 自己去補」。
Which（哪一個）：當疑問詞時要有一組已知的選項讓人挑，本句沒有；當關係代名詞時前面要有先行詞，而空格前面什麼都沒有。Where（哪裡）：副詞性的字，填不進 learns 後面那個受詞的洞，整句也與地點無關。While（當……同時）：從屬連接詞，帶出的是副詞子句，副詞子句不能拿來當句子的主詞。
be known to sb（為某人所知）、be known as（以……的身分為人所知）、be known for（以……著稱）、learn sth from sb（向某人學到某事）、at once（立刻）、one mind（想法一致、同一個心思）。
It is a usual sunny afternoon in the village of Midwich, England. It seems not 21 any afternoon in the village, but all of a sudden, people and animals lose consciousness. 22 they awake, all of the women of child-bearing age have become pregnant.
This is an episode from a 1960 science fiction story. The women in the story 23 birth to children that have the same appearance. They all have blond hair and "strange eyes." 24 the children grow, they run around the village in a pack, wearing identical clothing and hairstyles, staring at everyone impolitely. 25 one child learns is also known by the others instantly. Villagers begin to 26 their belief that the children all have "one mind."
In this story, the children are produced by some unexplained force from outer space. But this story written 40 years ago 27 predicted the arrival of a recent method of genetic engineering—cloning. Cloning is the genetic process of producing copies of an individual. Will the genetic copies of a human really have "one mind" as 28 in this story? This situation is so strange to us that we do not know what will 29 of it. Faced with this new situation, people have 30 to find out how to deal with it.