a.[B]

1. 中部的，中間的
   They sat in the middle row.

   他們坐在中間一排。

2. 中等的，中級的
   He was a man of middle height.

   他是中等個子。

3. （大寫）中古的

n.[C]

1. 中部，中途；中央[the S]
   I was in the middle of my work when he called.

   他打電話來的時候，我正在忙。

   It is already the middle of summer.

   現在已是仲夏了。

2. 【口】（人體的）腰部

vt.

1. 把……放在中間；把……對摺

vi.

1. 放在中間；對摺

adj.

1. at an equal distance from the extremities of something; central.
   ▸(of a member of a group or series) placed so as to have the same number of members on each side:

   he was in his middle forties.
   ▸intermediate in rank, quality, or ability.
2. Grammar  denoting a voice of verbs in some languages, such as Greek, which expresses reciprocal or reflexive action.

n.

1. a middle point or position.
2. informal a person's waist and stomach.
3. Grammar  a middle form or voice of a verb.

v.