What researchers such as Ransom Myers and Boris Worm have shown is just how fast things are changing.

　　【析句】這句子中，what引導(dǎo)主語從句，is是謂語，how引導(dǎo)的從句做賓語。

　　That means a higher proportion of what is in the sea is being caught, so the real difference between present and past is likely to be worse than the one recorded by changes in catch sizes.

　　【析句】這是一個(gè)因果關(guān)系的復(fù)雜句，what引導(dǎo)的從句修飾propotion。