Verbs lesson 1
"Creo que tiene dos hijos" I responded " I believe you have two sons" was marked wrong and Computer responded "He has two sons, I believe" Is the case of better and best?
I am under the impression that all new course content starts with only one pair of sentences. If you don't answer with precisely the expected sentence (except for upper/lower case, diacritics and punctuation), then it's marked as wrong. When you encounter this situation you are supposed to submit your alternative correct solution.
In other words, we are not just being offered a great Spanish course here for our consumption, we are also being crowd-sourced to help build it. I am not sure how they are using the information that we are submitting, but what would make sense is an automatic system that accepts or ignores these submissions automatically based on how many submissions there are of the same sentence and the acceptance track records of the submitting users. And to have a qualified native speaker of both languages look over the borderline submissions to fine-tune the system.
"Creo que TIENES dos hijos" is the translation for "I believe you have two sons"; "tiene" refers to the third person, "I believe he has two sons".
@friulana: You are right in principle, but your first sentence can also be short for "Creo que usted tiene dos hijos". Normally both answers are accepted as correct in this situation, and I can see no reason why this shouldn't be the case for this sentence as well. (Maybe this is different from Italian, for example. I guess that if we leave out the "Lei" in "Credo che Lei ha due bambini", the meaning will be changed completely rather than made ambiguous. Whereas with "io" this would definitely work.)