Mars 是独一无二的吧 !!! 只能用 Mars
earth 土地 === soil
(n) Potatoes grow in the earth/soil.
[ +the earth ] === 地球
The earth is round.
earthy (ADJ), of the earth (ADJ),earthen (ADJ)
on earth, earthworm (N)蚯蚓
Mars是一个单独的词,很特殊,只能单用Mars,给个例句:The aliens from Mars land on the Earth.
也想知道