1.3

Is there any rule to know when to say or not to say the words yo or tu ?Quiero means I want ,Yo quiero means I want ,(yo)hablo espanol ,hablo espanol. Also to say set before I want a tea dosen't seem to make much sense to me. Is there anything comparable in english?

As to when you need to use yo, tu, etc it depends on the verb tense. Take Comer here for an example http://www.spanishdict.com/conjugate/comer In some tenses such as the Imperfect the yo and tu form of the verb are the same. If context doesn't distinguish then you have to add the yo or tu to clarify. Set: perhaps English could be "[then it's] set! I want a tea"