This link does not explain why but it does show "pienso de"("to have an opinion about.") and "pienso en"("to think about") have different meanings. http://spanish.about.com/od/usingparticularverbs/qt/using_pensar.htm
You are correct. 'Escribo esto" can be correctly translated as 'I write this [simple present] or 'I am writing this' [continous present/present progressive]. This has been taught forever in academic language studies. In fact, the ways the present tense can be correctly interpreted – or used – may take you aback just a bit: See http://users.ipfw.edu/jehle/courses/PRESENT1.HTM
However, for its own reasons, DL, at least in the English-Spanish section doesn't currently allow for it. This is unexplained, but the intention may be, somehow, to avoid confusion with the Spanish present progressive, which is covered in these environs.
Additionally, "escribo" can be translated, "I do write".
So, "escribo" can be:
1 | I write
2 | I do write
3 | I am writing
Which helps in negations,
2 | I do not write
3 | I am not writing
2 | Do I write?
3 | Am I writing?
"escribo" is kind of a weird word to use in this case, especially for questions (it's obvious if you do or don't write), but syntactically, you'd switch the helping verb ("do" or "am") with the person/people performing the verb.
Gotta share, as a transplanted southerner, I had to start choking on my y'all, and say 'you guys' to avoid distracting teasing --which then sounds sexist to some... but then 'you folks' like 'you people' offends in an ethnic way.... why I choose writing over oral comm.... I can check-and-modify to avoid offense.
Fair question. The fact is that, just as in English, pensar (to think) and creer (to believe) have the same or similar meanings in some contexts, but diverge in others. In English, we (uh, well, some of us) often say "I believe ...such and such..." in a way that is synonymous with "I think... such and such." On the other hand "I believe in you" and "I (am) think(ing) about you" are significantly different things.
If Duolingo gives you the English example "I think of you," and you reply "Pienso en usted," and you are counted wrong, then it is then your duty to report that error to Duolingo to improve the community's learning experience and ensure that people of the future don't encounter the same frustration that you did.
However, if Duolingo gives you the Spanish example "Pienso in ustedes," and you are asking why it didn't give the example "Pienso en usted" instead because the correct answer given was "I think of you," then my response to you is that it's because in English "you" can be singular or plural, so it can be translated as "usted" or "ustedes."
Hey there Yen. If you want to say "I think of/about you (singular, informal)," then it should be:
Pienso en ti.
(since that's the correct pronoun to use as the object of a preposition)
If you want to clear up all of your doubts, you should follow these links to study up on the different types of pronouns that exist in Spanish and specifically what the prepositional object pronouns are.
Did you include the subject and verb "I'm?"
If so, Tejano already answered this question above. "I'm thinking of you" is a proper translation of "pienso en ustedes," however Duolingo doesn't accept the English present progressive tense as a valid translation of the Spanish simple present tense, maybe because they don't want us to get confused about the Spanish present progressive tense, which comes as a different lesson.
Correct, but there should be a tilde over the "n" in "sonar". Otherwise, it means "to sound".
Oh, sorry, I missed one thing:
You should have said "pienso en ti."
That's the second person informal prepositional object pronoun.
Because it just isn't. "To think of " or "to think about" persons or things is simply expressed with the appropriate idiomatic phrase derived from "pensar" + "en.." However, to think of/about something in the sense of having an opinion about it can be "pensar de."