1.terrestrial

adj.

[definition]:陸地的；陸棲的；陸生的；地球的--terrestrial creatures.

[synonyms]:earthly,worldly,telluric（源自地球的），global,native

[antonyms]:extraterrestrial（外太星的）

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2.mammal

n.

[definition]:哺乳類動(dòng)物；哺乳動(dòng)物類；哺乳動(dòng)物哺乳類動(dòng)物--aquatic mammal水生哺乳動(dòng)物.

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3.cetacean

n.

[definition]:鯨類--in cetaceans.

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4.speculate

v.

[definition]:投機(jī)；推測(cè)；猜測(cè)；推斷--it has been speculated that...

[synonyms]:wonder,conjecture,guess,hypothesize（假設(shè)）,reason

[antonyms]:know,decide

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5.blowhole

n.

[definition]:（鯨頭頂?shù)模┖粑?；（供海豹等呼吸的）冰窟?/p>

回顧：1.terrestrail 2.mammal 3.cetacean 4.speculate 5.blowhole