If there is no interpreter present you are not supposed to speak in an unknown tongue, as far as praying it is for your own edification, however, my church all pray together, as one, I cannot keep my mind on what I am praying for with everyone else praying at the same time, so I often times, slip into an unknown tongue. And for singing in an unknown tongue, I have not experienced that yet, but I did hear a lady sing one time and it was like Heaven had opened, it was the most beautiful thing that I have ever experienced, until my granddaughter, sang the answer to something that I was wondering about. She was about 5 at the time, and had not been around anyone who did that, ever. Don't even try to tell me it is not real...........I AM NOT HEARING YOU!! My being able and willing to yield to the unction of the Spirit, to pray in the Spirit, led to my brother in law and a friend he was working with not being seriously wounded or killed, it saved my daughter from being abducted by a man with evil intents, it brought help to me, when my car caught fire, it also brought help when my husband was seriously injured, and the car overheated on the interstate, it saved a girl from some kind of trouble, as she did not tell me what, but her expression told me all I needed to know, when I told her that the Spirit woke me up and told me to pray for her the night before, it brought my dog who had been hit and was laying in the ditch not moving, up and all the way up a flight of stairs, to his bed, then it kept him alive, when she was not able to eat anything for days and days, until she was completely well. and these are just a few of the things that I can remember over the years, yeah, you are talking to the wrong girl when you try to say the gifts of the Spirit are not for today.