First, read the English article below.

Most dogs are not aggressive, but, rather, just curious or defending what they perceive as their territory. Thus, to avoid unnecessary conflict, it is important to be able to tell if a dog is just playing or is being truly aggressive. While some breeds have been singled out as being particularly vicious, any mid-size and large dog breed can be dangerous, so do not ignore warning signs because you think a certain breed is harmless or friendly. Watch for common signs of aggression (and non-aggression):  Growling, snarling, and baring teeth are obvious displays of aggression and should be treated as such. An angry dog may show the whites of his eyes, especially if these aren't normally visible. Pulled-back ears laying flat against the head are a telltale sign of aggression, whereas normal floppy or elevated ears usually signal a dog's nonchalance. If the dog approaches you with its body relaxed and with a sloping curve in its midsection, the dog is probably not going to attack. A dog whose body is tense, straight and stiff (head, shoulders and hips aligned) could mean business. A loping gait means the dog is playful and checking you out.  An even, steady run means the dog may be dangerous. void aggravating a dog. Most dog attacks are the result of insufficient containment of the dog, poor training, or taunting. Unfortunately, the world will never be rid of bad owners, so it is wise to be prepared. Common sense should tell you not to aggravate any kind of animal.  Never irritate a dog who's eating or caring for her pups. Dogs are extra-protective during these times. Avoid smiling at the dog. You may think you are putting on a friendly face with a big toothy smile, but an aggressive dog sees you baring your teeth for a fight. Dogs that are chained or tethered to a stationary object for extended periods of time are more likely to be aggressive, so do not come within their reach. In general, the best policy when it comes to dog attacks is to do everything you can to avoid them in the first place. If you see a dog... 

Now, please write a short abstract for it in Vietnamese. Abstract:
Chú ý các dấu hiệu cảnh báo. Tránh trêu tức chó. Coi tất cả chó lạ là mối đe dọa.