句子改錯，我覺得是 designed for fighting, 不知是否正確，謝謝解答!

The body structure that developed in birds over millions of years is well designed for fight, being both lightly in weight and remarkably strong.

這是托福語法改錯題。一般這種改錯題不會是詞語錯誤而是語法錯誤。原題如下，題中原為flight而不是fight，可能是網友上傳時打字失誤。being的表語應為形容詞而不可以是副詞，故lightly是錯誤之處，應改為形容詞light。

The body structure that developed in birds over millions of years is well designed for

flight, being both lightly in weight and remarkably strong.