A stand with three legs is a tripod.
The Blue Crab has ten legs. They use the fifith set of legs to swim and the third set to walk. For further information go to: http://www.avivadirectory.com/trivia/213-20-fast-facts-about-blue-crabs
A stand with three legs called atripod
A dog stands up with four legs and two legs
That would be a tripod, which does indeed have three legs -- and is a stand.
it is a stand with 3 legs
It's just how they stand. Like us, for example. We stand on two legs, and they are probably saying "Why do humans stand on two legs?" It's just like asking "Why do dogs stand on four legs?"Please recommend me!
two legs
Yes, they can stand up on their hind legs and crawl on all fours.
octopus do not have teeth. they have beaks.
On the PlayStation 3, you have to press L1 and R1 at the same time and your Xenomorph (alien) will stand on it's back legs. It will stay like that for about 5 seconds and then go into block position. (you can't attack while on your back legs)
If you are finding that your legs get so numb that you are unable to stand, you should see a doctor. It is normal to get numb legs from sitting for long periods of time but you should be able to stand up.