A snowman was working a lot. 

 The snowman received a letter.

you are invited  to a tropical island

 It said that it was invited to a tropical island.

 The snowman was  very happy, and it went fast to its house to pack all the things.

The next day it went to the airport.

 In the airport got into the plane.

 When it arrived at the tropical island, it made another snowman.

 The other snowman asked if it wanted to go with it to a tropical island and it said yes.

They were walking and the volcano exploded

They ran a lot.

Finally, they protected themselves in a cave.

And when everything was calm, the two snowmen came out of the cave.

They saw a sad volcano.

 They hug it, and they asked about the reason it was sad

 The volcano said that it was sad because it had a trunk stuck in his back.

 The two snowmen removed the trunk from his back.

And they were friends forever.