'Think Big!': How would you translate that as an imperative?
The closest I have seen so far is: 'pensar en grande'. What about 'Piensen en grande' or 'Piensa grande'? Anyway, what is the imperative of 'pensar'? Piensa or piense?
james
4 Answers
The tú imperative form of pensar is "piensa". The usted form is "piense". Therefore, both are correct. It just depends on who you are addressing.
If you want to say "Think Big" using an imperative: You could say "piensa en grande" if addressing someone in an informal way [someone younger than you, a friend]. You could also say "piense en grande" if addressing someone in a formal way [your boss or an older relative]
Think Big"...this book's title is "Think Big" and it is translated to "Pensar en Grande"...click here to see the book

I think you got the right phrase: pensar en grande.
Piensa en grande = Think big (you, singular, informal)
Piense en grande = Think big (you, singular, formal)
Piensen en grande = Think big (you, plural, formal--Spain only; formal/informal--outside of Spain)
Pensad en grande = Think big (you, plural, informal--Spain only)
Edit: Added the vosotros conjugation for completion.
Mmmm... I say "piensa en grande" if I am talking in an informal way (tuteando or saying tu) and I say "piense en grande" if I mean to say (usted) formal way.

As Sonrisa says the verb infinitive is often used for imperative mood, especially in lists of instructions, recipes, etc.
