"Yes, I want two pens, please."
Translation:Sí, yo quiero dos bolígrafos, por favor.
Are there times when 'yo quiero' vs 'quiero' (for example) is more or less appropriate? Or is 'yo' only used in formal or emphatic speech, perhaps? Personally, I would just drop 'yo' from most statements except where emphasis or formality is required, but would that be correct?
You should try and avoid using 'yo' as much as possible because it starts to make you sound a bit self important! I, I, I, I etc. Usually it's only ever used for clarification as to who is doing the action where confusion might arise.
This is a really useful guide to personal pronoun use:
I am a Spanish native speaker.
It depeans of the Spanish that you would like to learn. In Spanish from Spain (I am from Spain) we use bolígrafos. Pluma is correct but it doesn't sound natural (in Spanish from Spain).
Pluma is common in some Latinoamerican Spanish speaking countries thought