1.variation

n.

(资料图)

[definition]:变异；变体；变奏；变种--seasonal variation,genetic variation,temporal variation,slight variation,wide variation.

[synonyms]:difference,disparity,dissimilarity,distinction,discrepancy

[antonyms]:similarity

2.reference

n.

[definition]:参考；编号；提到；查询--get reference,make reference,contain reference,provide reference,give reference,positive reference,direct reference,oblique reference,important reference,reference brief

3.inhabit

v.

[definition]:居住(在)；栖息(在)；占据；充斥--growing to two or three inches long, krill provides the major food for the great blue whale, the largest animal to ever inhabit the Earth越来越两三英寸长，主要渔获为粮食大蓝鲸，最大的动物都生活在地球上.

[synonyms]:live,dwell,occupy,reside,populate

4.deteriorate

v.

[definition]:退化；变质；败坏(风俗)；降低(品质等)

[synonyms]:decline,depreciate,fade,fail,get worse

[antonyms]:improve

5.echolocation

n.

[definition]:（尤指海豚、蝙蝠等动物的）回声定位

回顾：1.variation 2.reference 3.inhabit 4.deteriorate 5.echolocation