There are numerous Class M planets in the galaxy. Most of them have humanoid inhabitants. And these aliens all speak English. They also have attractive females who catch the eye of Captain Kirk.
Col. O’Neal and the gang showed a lot of habitable worlds spoke English and many looked like backdrops for Renaissance fairs.
However, as soon as you beam down to the planet's surface, you'll find that your phasers and communicators no longer work. Also, you can't get back to your ship until you find the main power source on the planet and knock it out. Fortunately, you will have beamed down to within 15 feet of the main power source.