1. infest v. (of something harmful, dangerous, or unwanted) to be present (in a place) in large numbers or to a great degree (大量危害物)出没于; 侵扰; 骚扰: It would be crazy to swim in these shark-infested waters.
swarm: The place was swarming with tourists.
teem: This river teems with all kinds of fish in summer.
overrun: The stables are overrun with rats.
beset: The plan was beset with difficulties from the beginning.
2. habitat n. the natural home of a plant or animal (动植物的)栖息地或产地: I prefer to see animals in their natural habitat, rather than in zoos.
habitation: The dilapidated hut is unfit for human habitation.
habitable: Their damp house is scarcely habitable.
uninhabitable: The planet Jupiter is uninhabitable.
inhabit: Woodpeckers inhabit hollow trees.
3. torpid a. (esp. of an animal that sleeps through the winter) having lost the power of feeling or moving; lazy or inactive; moving or thinking slowly (冬眠动物)失去活动能力的; 处于蛰伏状态的: The heat and humidity made us feel torpid.
lethargic: The weather made her listless and lethargic.
sluggish: sluggish traffic; a sluggish economy
dormant: During the winter the seeds lie dormant in the soil.
latent: These children have a huge reserve of latent talent.
4. lifespan n. the average length of life of a sort of animal or plant or the time for which a material object will last (动植物的)平均寿命; (物品的) 使用年限: Men have a short lifespan than women.
life expectancy or expectation of life 预期寿命; 平均(期望)寿命:
Life expectancy for men is about 78 years in Japan.
span n. 指一段时间或(桥梁)跨度/全长: attention span; memory span;
an unbroken span of concentration; The bridge crosses the river in a single span.
span v. 跨越/横跨; 延伸/贯穿: His interests spanned a wide range of
subjects. The game has a history spanning three centuries.故lifespan的直意为＂生命的跨度＂
5. metabolism n. the system of chemical activities by which a living thing gains power(energy), esp. from food 新陈代谢: The metabolism is slowed down by extreme cold.
metabolic: People who have inherited a low metabolic rate will gain weight.