Esperanto is an international artificial language.

He can speak Finnish.

I have started learning Hebrew.

I am thinking of learning Greek.

His native language is Spanish.

They are using English as a common language.

He always speaks in polite language, so he is considered very courteous.

His laughter can be expressed with the onomatopoeic word 'gyahaha'.

The water of this river is muddy.

The result of the game is fifty-fifty.