不加。family作“家人”時表示復(fù)數(shù)概念，作主語時，謂動用復(fù)數(shù)；family一詞不用復(fù)數(shù)形式。family作“家庭”時，表示家庭這個整體，是單數(shù)概念。作主語時，謂動用單數(shù)；family作“家庭”時，有復(fù)數(shù)形式，families表示幾個家庭。

family的意思是“家庭，家庭成員”，與居住的房子無關(guān)。

family作整體概念的“家庭”講時是單數(shù)；作“家庭成員”講時是復(fù)數(shù)。

例如: Bob has a big family.

鮑勃有一個大家庭。（family做“家庭”講）

My family are very well.

我的家人都很好。（family做“家人”講）

There's room in there for a family of five.

那兒能住得下一家5口。（family做“家庭”講）

Does he have any family?

他有什么家人嗎？（family做“家人”講）

His family have been a very positive influence on him.

他的家庭對他有十分良好的影響。

Families will be better off under the new law.

新法律會使家庭經(jīng)濟(jì)寬裕一些。

I always think of you as one of the family.

我一直把你當(dāng)成自家人。

We think of you as one of the family.

我們把你看作家中的一員。

Their family has always been well thought of around here.

他們家在這一帶一直頗受敬重。