You Needn't capitalize the o inside the word "a single" if it isn't the initially term of a sentence. The tutorial you viewed is appropriate. The explanation the 1st sentence is ungrammatical is because it is often a operate-on sentence, and that is a very common grammar error. BravoBravo sixteen.2k2525 https://vodemcasa.com/one-tv-p2p-plano-semestral