Here are some sentences on Robinson Crusoe I'd like you to check. Thank you.

1) After rowing for seven kilometres, a huge wave took the boat and threw them into the air like a ball.
2) Robinson fell into the sea, water filled his mouth (his mouth was filled with water?) and he could hardly breathe.
3) Though they waves pushed him throwing him against the rocks, he managed to reach the beach.
4) By moving on his hands and knees, he got to a place where the waves couldn’t reach him and sat on the grass.
5) The following morning the weather was fine again and he realized that the ship was still there, about one kilometre away from the beach.

2. Delete the stuff in parentheses, and put a comma after "mouth"

3. "Though the waves..." -- comma after the first "him"

4. "and sat on the grass" needs a subject -- otherwise, it reads as if the waves were sitting on the grass!!

5. comma after "again"

Here are the corrected sentences:

1) After rowing for seven kilometers, a huge wave took the boat and threw them into the air like a ball.

2) Robinson fell into the sea, water filled his mouth, and he could hardly breathe.

3) Though the waves pushed him, throwing him against the rocks, he managed to reach the beach.

4) By moving on his hands and knees, he got to a place where the waves couldn't reach him and sat on the grass.

5) The following morning, the weather was fine again, and he realized that the ship was still there, about one kilometer away from the beach.

If you have any further questions, feel free to ask!