Question

why dogs are genrally hangout their tongue

Answer 1

We generally notice dogs hanging their tongues out.

As, we all know that these are days of summer. We notice that sweating is more frequent during these days.

Sweating is highly useful for us. During warm days, in course of time or due to exercises or some other reason our body gets warmed up more quickly. To prevent this malfunction our body stars sweating. The sweat drops usually evaporate and produce a cooling effect on the surface of our body thus bringing it's temperature down.

Dogs lack this mechanism, so to prevent this they hangout their tongues to take more air into their body so as to bring down the temperature of their body. That's why they generally hangout their tongues.