Sprawdzenie krótkiego listu nieformalnego

Proszę o sprawdzenie poniższego listu.

Dear Tom,

How are you ? I hope you're well. I'm sorry that I haven't written to you for such a long time but I've been busy preparing for my exams.
I'm writing to tell you about the pop concert which took place in my town last week. I was surprised because the audience was really large. People singing and dancing all the time. Also I was delighted with friendly atmosphere. I enjoy listening to music, so I played great. I'm looking forward to next concert, maybe can you go with me ?
Unexpectedly, I saw my childhood best friend, Kate. It was quite shocking meeting for me because I haven't seen her for five years. We sang and laughed together, it was very fun.
Unfortunately, I must finish this letter.
Greetings to your girlfriend.
See you,
Xyz

Czy mógłby ktoś sprawdzić cały powyższy list, łącznie z dwoma zdaniami które zmieniłam ?
"I was surprised because the audience was really large. People singing and dancing all the time." na
- I was surprised by such a huge audience
- People sang and danced all the time

"People singing and dancing all the time" - brak czasownika

"I was delighted with friendly" - zmień podkr.

"I enjoy listening to music, so I played great" - to był twój koncert ? jeśli nie to "I like listening to music, so I enjoyed the time (I had a great time).

"maybe can you go with me" 1. zła kolejność (you can), 2. maybe z can ? może możesz....to już lepiej could, ( to zdanie powinno być pod koniec listu, przed "Unexpectedly")

"Unexpectedly, I saw my childhood best friend, Kate" - ale gdzie?

"Unfortunately, I must finish this letter" - "must" za mocno tutaj, uzyj "have to"

- użyłabym continuous

People has been singing and dancing all the time.
a tak napisac można ???
Pa. Cont. najlepiej pasuje.

Czy może być tak ?
When I went to get something to drink, unexpectedly I saw my childhood best friend, Kate

nie użyłabym "has been doing" mówimy o zakończonej czynności w przeszłości, bez skutków w teraźniejsości jeśli tak można powiedzieć

w 1 części użyłabym Past Cont.bo inacej "when" nie pasuje

dziekuję bardzo :)

??

Brakuje przedimkow - prosze poprawic.....
Unexpectedly, I saw my childhood best friend, Kate.- to zdanie jest zle zformulowane.
It was quite (brak cos) shocking meeting for me because I haven't seen her for (the last) five years. We sang and laughed together, it was very 'fun' (to jest zla czesc mowy).

własnie też tak myślałem, ale wolałem się zapytać.
Kto pyta, nie błądzi :)

Mozna tez zostawic "fun" i zastapic "very" czyms innym.