He/She probably saw a bird.
If there was nothing in the sky when he/she started barking, and he/she is in the middle of a field with nothing surrounding it, then it could be that he/she has some problems.
If he/she is barking from your backyard then it might be there is a noise coming from the roof. It could a squirrel...
Examples of the sentence using pronouns.It barks at the cat.The dog barks at it.He barks at the cat.The dog barks at her.She barks at him.
A dog barks while a frog croaks.
barking
"Hello, how are you?" Woof.
A seal ! (or a dog !)
dog
bark back
I am guessing a seal
get a muzzle maybe? (for the dog obviously) :)
"A dog will bark" is that sentence in the future tense.
A puppy barks at everything. Older dogs know better. They only bark at things that are not normal, such as a burglar or something wrong. This phrase means that when an old dog barks, it means something.
obama on his knees