functions是什么意思

例句：

The sofa also functions as a bed.

这沙发还可当床用。

My camera has manual and automatic functions.

我的照相机有手调和自动两种功能。

Both motor and sensory functions are affected.

运动功能和感觉功能都受到影响。

The hall provided a venue for weddings and other functions.

大厅给婚礼和其他社会活动提供了场所。