1.sheath n．鞘(a case for a blade( as of a knife))；防护物(sheathing)
例：It is possible that many prehistoric microbes evolved without significant modification of their sheaths.
2.shed v.脱落（即蜕皮）(discard)；流出，散发（to give off or out）
例：Until they are fully grown, horseshoe crabs(马蹄蟹)shed their shells and grow new ones several times a year. ll shed warmth and light发光发热
3.sheer a．薄的(thin)；纯粹的(pure)
例：sheer curtains 薄窗帘//sheer brandy纯正白兰地
4.shellfish n.甲壳类动物(an aquatic invertebrate animal with a shell)
分拆记忆：shell(壳)+fish(鱼)--甲壳类动物
例：As envisioned by researchers, commercial farming of lobsters will enable fisheries to sell the shellfish year-round.
5.shelter n．躲避处(a protective structure)；v.庇护，保护(protect)
例：food, clothing, shelter and transportation衣食住行//The blue butterfly depended on the nests to shelter its offspring.
6.shield n．盾(a broad piece of defensive armor carried on the arm);保护物(protector);y．(from)保护(protect);挡开(defend)
记：要牢记shield的原始意义“盾”，其他意义均可引申而来
例：lf the protective shield is not in place, the machine will not operate. //The patents can shield patent-holding manufacturers from competitors.
派生词：windshield(n．挡风玻璃)
7.shimmer n．微光，闪光(a light that shimmers);讥使闪烁，发闪烁的微光(to glimmer)
联想记忆：她站在夏天( summer)的夜空下看星星闪烁(shimmer)发光
例：The shimmer and sheen of both fabric and skin depend on the geometry of their internal structures-the exact arrangement of threads or protein fibres.
8.shortfan n．亏空(deficit)：不足(shortage)
联想记忆：short(短)+fall(下落)--因收入下降而短少--亏空
例：The new policy of tax cuts issued by the government resulted in a shortfall in Federal revenues.//There will be a shortfall in wheat supplies this year.
9.shrill a．（批评）尖锐的(sharp)；刺耳的(piercing)
例：shrill criticism尖锐的批评//a shrill whistle刺耳的汽笛声