Giving your opinion in Spanish

Someone says the new bus lane is a disaster. You want in. Three openers do almost all the work: creo que…, me parece que… and para mí…. So: creo que funciona bastante bien, me parece que es demasiado pronto para saberlo, para mí es una buena idea.

Then the reactions. Agreeing: estoy de acuerdo, tienes razón, exacto. Half-agreeing, which is where real conversation lives: sí, pero…, depende, en parte sí. Disagreeing: no estoy de acuerdo, or the softer yo lo veo de otra manera.

This is the core of the lesson, so read it twice. After an affirmative creo que the next verb is the ordinary indicative — exactly the forms you already know: creo que es buena idea, creo que tiene razón, me parece que funciona.

Negate the opinion verb and the next verb switches to the subjunctive: no creo que sea buena idea, no creo que tenga razón, no me parece que funcione. Compare them side by side: es against sea, tiene against tenga, funciona against funcione. The trigger is not doubt in your head — it is the word no in front of the opinion verb. There is no no creo que es.

You do not need the whole system yet, only the handful of verbs that come after no creo que every day: sea (ser), esté (estar), tenga (tener), haya (haber), pueda (poder), vaya (ir). For regular verbs, swap the vowel: funciona becomes funcione, come becomes coma.

If you want to avoid the subjunctive entirely for now, there is an honest way out: state the negative directly. Creo que no es buena idea keeps the indicative, means almost the same thing and is very common in speech. Use it while the subjunctive settles.