How do you say 'I think' in Spanish?

(1st Answer)

(Yo) pienso - I think

You can add a 'que' for i think that

(2nd Answer)

There are two spanish verbs for think.

Creer and Piensar

Use Creer when you want to say something as in "I think so" or "I believe so"

Use creer when you say "think" as the Word "believe" , like you believe something.

I (think/believe) so = Creo que si

Use Piensar when referring to your thoughts and your thinking.

I think in spanish. = Pienso en espanol.

thought = pensamiento