① 在 such 或 so + 形容词与单数可数名词连用时，不可缺 a (an)。如：
He is such ∧ (an) honest boy that all of us like him.
This is so good ∧ (a) book that I read it again.
② 表示“有些”时，little, few前面不可缺少 a。如：
Don’t hurry. There is ∧ (a) little time left.
③ many 前有 great, good 时，要加 a。如：∧(a) great many people.若 many 后接单数名词，中间须有 a (an)。如：Many ∧ (a) man has tried it before.
④ 一些不可数名词前，有形容词修饰表示“一种(场)等”时，要加 a (an)。如：
It’s ∧ (a) famous Chinese tea.
There was∧ (a) heavy rain last night.
⑤ 用专有名词表示“一个像(叫)……的人”时，用 a (an), 如：
He wished to be ∧ (a) Lei Feng.
∧ (A) Mr Wang called you up just now.
⑥“形容词比较级 + of the two…”前必须用 the。如：
He is ∧ (the) better one of the two.
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