About 60 million years ago Gondwana broke up into 27 later became South America, Africa, Antarctica, India and Australia.
答案：(C) what
what 是複合關係代名詞，本身就等於「先行詞＋關係代名詞」（＝the things which），介系詞 into 後面沒有先行詞，只能用 what；which、that 前面必須有先行詞，where 引導地方副詞子句，都不合。
答對率 23%。
看到空格後面接動詞 later became，你知道要填關係代名詞，卻反射性地挑 which 或 that——因為課本教的關係代名詞都長成「先行詞＋關代」的樣子。這一題的關鍵在於：空格前面是介系詞 into，前面根本沒有先行詞。
what 是複合關係代名詞，本身就內含先行詞，等於 the thing(s) which／that。所以 into what later became South America, Africa… ＝ into the landmasses which later became…（分裂成後來變成南美洲、非洲…的那些陸塊）。which 與 that 前面一定要有先行詞，這裡沒有；where 引導的是地方副詞子句，後面不能直接接動詞當主詞。
空格前面是介系詞或及物動詞、後面直接接動詞，而且往前找不到先行詞——答案通常就是 what。
國中學過 What he said is true.（他說的話是真的），句首那個 what 就是同一個複合關係代名詞，等於 The thing which he said；也學過 This is what I want.。本題只是把它擺到介系詞 into 的後面而已。
what（＝the thing which，複合關係代名詞）、Do what you like.（做你喜歡的事）、what is called（所謂的）、what is more（更有甚者）、what is worse（更糟的是）。
Up to about 250 million years ago the world had just one huge super-continent called Pangaea. Animals were able to move and intermix with 26. About 200 million years ago this super-continent broke up into two continents: Laurasia and Gondwana. About 60 million years ago Gondwana broke up into 27 later became South America, Africa, Antarctica, India and Australia.
Since then Australia 28 from the rest of the world by vast oceans. The animals there no longer had 29 with animals from other parts of the world. They evolved separately. As a result, about 95 of Australia's mammals and 94 of its frogs are found 30 else in the world. Australia has lots of very unusual animals.