Не окончание,а суффикс «ing” окончания там нет
[ eɪ ]: an alligator, a whale, a ladybird, a raven, a snake.[ æ ]: a dragonfly, a rat, a panda, a crab, a hamster, a parrot, a bat, a panter, a rabbit.
Jack, Ryan, Lewis, Ewan, Harry
3) happened, saw
4) written
6) smoked, gave up, didn't touch
8) set off, got, waited, waited
10) broke, dropped, climbed