medium
a.中等的 n.媒介物;新闻媒介;手段，工具
What size shirt does he wear – small, medium or large?他穿多大的衬衫 – 小号，中号还是大号?
deprive
vt.(of)剥夺，使丧失
A lot of these children have been deprived of a normal home life.
这些孩子中有许多被剥夺了正常的家庭生活。
derive
vt.取得;追溯起源 vi.(from)起源，衍生
Medically, we will derive great benefit from this technique.从医学的角度来讲，我们将从这一技术中受益匪浅。
descend
vi.下来;(from)起源;(to)沦为 vt.走下
Our plane started to descend.我们的飞机开始下降。
describe
vt.描写，形容;画出(图形等)
The police asked her to describe the man.警察叫她描述一下那名男子。
