The old man walked . . . . . . . . the road slowly. Which preposition is suitable to fill the blank?

You should not trifle . . . . . . . . his feelings.

Let's discuss . . . . . . . . the ways of improving the basic skills of English.

The books are . . . . . . . . my schoolbag.

Unfortunately, we had to cancel it owing . . . . . . . . the bad weather.

He turned his back . . . . . . . . her.

Kathleen apologized . . . . . . . . her brother's poor behaviour.

He lives . . . . . . . . Australia.

The man was charged . . . . . . . . murder.