Aufsatz: Korrigieren, bitte

Hallo,
ich schreibe eine kurze weiterführende Geschichte.
Könnte da jemand drüber schauen und kurze Anmerkunegn machen? Das wäre super nett...Und wie kann man "es könnte wertvoll sein" übersetzen? Vielen Dank!

Antonio

After one hour he opened his eyes. He lay (lie) in the sand of the beach. The hot sun shone (shine) in his eyes. Many sailors lay (lie) next to him. Then he saw (see) a ship that/which wasn`t smashed.
A lot of sailors went (go) to the ship. He went (go) to it, too.
The captain said (say):” Sorry, you can`t go on the ship. We haven`t enough place. But when we are get back to Havanna, we will come back and bring more ships to save you!”
Antonio was shocked! It is a three-week trip to Havanna and back. He went to the other sailors and told (tell) them:” We only can survive together!” So they built (build) houses and waited, that the ships come back. Some of them were (are) very nervous, because they thought (think), that the ships will never come back and they (were) are lost on this island. But 3 weeks later the ships came (come) back and saved them all. Antiono sailed (sail) never again.

Ryan
Ryan said (say):” We must show the coin to grandpa. It could (can) be very valuable.” Emely answered exciting: ”Yes – ok!” So they went (go) to grandpa. On the way Emely fell (fall) over something in the sand. It was very big. Emely shouted: “What was that?” Ryan came (come) to her and looked at it. “It is something out of metal. Maybe a treasure?”, he asked himself. They both began (begin) to dig with their hands. After a few minutes grandpa came (come) and they shoveled together. Some minutes later they found (find) an old chest. The chest was closed and they couldn`t open it. But they had luck – grandpa had a universal key. They opened the chest carefully and there were a few of gold coins and a letter: “ I hope, this treasure is now in good hands!” Captain Jonas
“Wow!”, Ryan thought. We are so lucky!