Acts 2:So you do not admit that they were all praising God, magnifying God, praying to God?
Acts 2:6 Now when this was noised abroad, the multitude came together, and were confounded, because that every man heard them speak in his own language.
Acts 2:11 Cretes and Arabians, we do hear them speak in our tongues the wonderful works of God.
--In this case they were praising God. It got the attention of a crowd that numbered about 100,000. They were accused of being drunk. It gave Peter the opportunity to preach.
Acts 10
Acts 10:34 Then Peter opened his mouth, and said, Of a truth I perceive that God is no respecter of persons:
Acts 10:44 While Peter yet spake these words, the Holy Ghost fell on all them which heard the word.
Acts 10:45 And they of the circumcision which believed were astonished, as many as came with Peter, because that on the Gentiles also was poured out the gift of the Holy Ghost.
46 For they heard them speak with tongues, and magnify God. Then answered Peter,
Acts 10:47 Can any man forbid water, that these should not be baptized, which have received the Holy Ghost as well as we?
--They spoke with tongues and magnified the Lord.
The purpose was the same as in Acts 2. Verse 45 states "they of the circumcision which believed were astonished...because that on the Gentiles also was poured out the gift of the Holy Ghost.
It was a sign to the Jews that the Gentiles had received the message of God. Otherwise they (the Jews) would not have believed. They were astonished at this event.
Acts 19
Acts 19:1 And it came to pass, that, while Apollos was at Corinth, Paul having passed through the upper coasts came to Ephesus: and finding certain disciples,
--Apparently the ones in this incident had been influenced by the preaching of Apollos (ch. 18) who also did not have a full understanding of the gospel.
Acts 19:2 He said unto them, Have ye received the Holy Ghost since ye believed? And they said unto him, We have not so much as heard whether there be any Holy Ghost.
--They were disciples of John the Baptist but had never heard of the Holy Spirit.
Acts 19:3 And he said unto them, Unto what then were ye baptized? And they said, Unto John's baptism.
4 Then said Paul, John verily baptized with the baptism of repentance, saying unto the people, that they should believe on him which should come after him, that is, on Christ Jesus.
--They still believed on the one who was to come.
Acts 19:4 Then said Paul, John verily baptized with the baptism of repentance, saying unto the people, that they should believe on him which should come after him, that is, on Christ Jesus.
--We infer here that salvation was explained more carefully to them.
Acts 19:5 When they heard this, they were baptized in the name of the Lord Jesus.
6 And when Paul had laid his hands upon them, the Holy Ghost came on them; and they spake with tongues, and prophesied.
--It doesn't not specifically give content of what they said or what they prophesied. Remember they had already been taught some by Apollos. This was a different situation.
The above three incidents are all historical, telling what happened and why. They all involve Jews, and how the gospel went out to certain Jewish groups.
In 1Cor.12-14, time had passed. The doctrine of the "gift of tongues" for the church had been established. Paul is teaching about spiritual gifts not the history of the church. It is a completely different scenario. In the above three cases there was a sudden miraculous happening, but not necessarily any gift was given.
In 1Cor.12-114 Paul speaks of gifts that were distributed among the members of the church. That is the difference. Tongues in every case, both in Acts and in 1Cor. are always known languages, as they are translated in the ASV and other translations.