n.騎兵(隊)

I am a soldier of the fourth cavalry. 我是第四騎兵部隊的一員。

The cavalry is extremely majestic-looking. 這支騎兵部隊非常威風凜凜。

They were taken in flank by a troop of cavalry. 他們的側翼受到一隊騎兵襲擊。

cavalry是集合名詞，用作主語時，如側重整體謂語動詞用單數(shù)形式，如側重個體謂語動詞用復數(shù)形式。