自2010年至今的四级考试中， 共出现过 次
自2010年至今的六级考试中， 共出现过 次
(蛋、坚果等的)壳 The shell of a nut or egg is the hard covering which surrounds it.
They cracked the nuts and removed their shells...
Once the eggs have hatched the shells are left behind.
(龟、蜗牛、蟹等的)壳 The shell of an animal such as a tortoise, snail, or crab is the hard protective covering that it has around its body or on its back.
贝壳 Shells are hard objects found on beaches. They are usually pink, white, or brown and are the coverings which used to surround small sea creatures.
I collect shells and interesting seaside items.
剥…的壳;去…的皮 If you shell nuts, peas, prawns, or other food, you remove their natural outer covering.
She shelled and ate a few nuts.
自我封闭的外壳;保护壳 If someone comes out of their shell, they become more friendly and interested in other people and less quiet, shy, and reserved.
Her normally shy son had come out of his shell.
...a lonely boy struggling to emerge from his shell.
(建筑物、车、船等的)骨架，框架，壳体 The shell of a building, boat, car, or other structure is the outside frame of it.
...the shells of burned buildings...
The solid feel of the car's shell is impressive.
炮弹 A shell is a weapon consisting of a metal container filled with explosives that can be fired from a large gun over long distances.
炮轰;炮击 To shell a place means to fire explosive shells at it.
The rebels shelled the densely-populated suburbs near the port.