1)
They let Peter sit on their tale and they let Peter to have a conversation between them and him (je ne suis pas sûr pour la seconde mais parce que c'est écrit "except of
course Peter, who chatted with them on Marooners’ Rock by the hour", and "sat on their
tails")
2)
The children usually go there in summer
3)
Most of the time the children go for swimming or floating; and playing the mermaid games in the water.
4)
After lunch, the children had to rest. So they rested on a rock
for half an hour.
Voilà ce que je pense :)
a+