earth/ɜːθ $ ɜːrθ/

n.

➊ [or (the) Earth] the planet on which we live

➋ the substance that plants grow in; soil

n.

➊ [或(the) Earth] [S] 地球：The earth revolves around the sun. 地球绕着太阳转。

◇This is the most beautiful place on earth. 这是地球上最美的地方。

◇the planet Earth地球

➋ [U] 土，泥：a lump of earth 一块泥土

◇Put the seeds in the earth. 把种子种到土里。

on earth 到底，究竟：[用于what, who等疑问词之后，加强语气] What on earth do you mean? 你究竟是什么意思？

常犯错误

✗ What on the earth is she talking about?

✓ What on earth is she talking about? 她到底在说什么？

[✌表达“究竟”之义时，用on earth，表达“在地球上”时，可用on the earth或on earth]

用法与其他星球比较用时，常大写，如Mars and Earth。

辨析earth; world