Как по Английски будет 附加功能

noun

An item in addition to what is usual or strictly necessary.

Примеры использования:

I had an education with all the extras

adjective

Added to an existing or usual amount or number; additional.

Примеры использования:

They offered him an extra thirty-five cents an hour

adverb

To a greater extent than usual; especially.

Примеры использования:

He is trying to be extra good