@stpaul , there are several ways of using the charism of speaking in tongues .
It can be used to convey a message , so on a few occasions I have heard someone speak in tongues with someone interpreting it .
Often I have heard people use the charism to pray in tongues . “For he that speaketh in a tongue, speaketh not unto men, but unto God: for no man heareth.” (1 cor 14:2)