This is John. This is his book. This is John's book.
These is my parents. This is their house. This is my parents' house.
This is Ron. This is his wand. This is Ron's wand.
Потому что это герундий. Иногда перед герундием может стоять предлог, в данном случае "by playing" означает "проигрывая" (деепричастие) или "путем проигрывания".
Puma — a type of family cat's. Paws wide, with sharp, curve vtyazhny claws; on hinder legs up to 4 fingers, on lobbies — on 5. Claws are used by Vtyazhnye for capture and production deduction, and also for a lasagna on trees. Small pillows of fingers oval, on a heel small pillow three distinct shares — a common feature for all cats.
<span>Contrary to ordinary opinion, a puma — quite silent animal. The loud cries similar to human shouts, it publishes only during the marriage period...
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I can read.
I can swim.
I can't ride a hors.
I can walk.
I can't cook.
I can jump.
I can sing.
I can't play the guitar.
I can't fly.
I can't drive.