deplete

vt.耗尽，使衰竭（exhaust)

I always replenish my food supply before it is depleted.

我总是在食物耗尽之前补充食物。

ebb

vi.衰退(decay)

The water washed up on the shore, then slowly ebbed away.

水被冲上海岸,然后慢慢消退。

enervate

vt.使衰弱(enfeeble, weaken)

The dullness of the lecture as well as the heat of the day enervated the students, who were all too tired.

讲座的乏味和天气的闷热使学生们感到疲倦，他们太累了。

languish

vi.变衰弱 (wither, fade)

The prisoners have been languishing for years in the dungeon.

囚犯们在地牢里苦苦思念多年。

debility

n.虚弱，衰弱

After operation, it seems that the old man was still in debility and had not recovered yet.

手术后，老人似乎仍然虚弱无力，还没有恢复。

feeble

adj.虚弱的，衰弱的 (weak, frail)

I felt feeble when I was ill.

我生病时感到很虚弱。

decay

n./vi.腐朽，腐烂；衰减，衰退

Dentists advise their patients to brush and floss regularly to prevent their teeth from decaying.

牙医建议他们的病人定期刷牙和用牙线洁牙，以防止牙齿腐烂。

wither

vt.（使）枯萎，调谢 (deteriorate)

The flowers withered in the cold.

花在寒冷中枯萎了。

recessionary

adj.（经济）衰退的，衰退期的

wane

n./v.（月）缺 ； 袞落(abate, diminish, lessen)

The tide was near the turn and already the day was on the wane.

潮水快转向了，一天已经过去了。