The correct sentence is He is allowed to do it on his own.
You cannot craft collars in Minecraft. By making a wild wolf a domesticated dog, it will automatically be given a collar. Unfortunately you cannot craft your own. To get a wild wolf to be your pet dog, just feed it meat or bones.
You already own a bicycle.
I can only guess at what you are trying to say, but I guess that this sentence should have been, understand it in your own home. You don't have to go to school to learn about this; you can understand it in your own home.
I own a sea dog.Come here, you salty old sea dog.
Do you own a computer? Grammatically it makes sense as a question. You do own a computer would be a suitable answer.
Yes, I can use "his" twice in a sentence: He gave his dog his favorite toy.
No. This is a clause that cannot stand on its own. It is not a complete sentence. A sentence needs a subject and a verb.
Every dog has its own personality, and the amount of training required varies accordingly. Most dogs will be trained in a few sessions. a hour
Yes, you can end a sentence with the word "own." It is grammatically correct to use it to indicate possession or agency, such as "She wanted to create a space of her own."
The little dog was having fun chasing his own tail.
He was afraid of the dog because it was a lot fiercer than his own one.