Why is dudo que with subjunctive, but no dudo que with indicative?

Question

Same question with creo que and no creo que. What is the difference? Why is one subjunctive but the other indicative?

Answer 1

Dudo que Gabriel VAYA al concierto (= I doubt that Gabriel goes to the concert).

"Dudo que" uses subjunctive because it introduces doubt or uncertainty. Other such phrases include "espero que", "es posible que", etc.

No dudo que Gabriel VA al concierto (I have no doubt that Gabriel goes to the concert). "No dudo que" uses indicative because it expresses clarity and certainty. Other phrases include "estoy seguro que", "es cierto que", etc.

Hope this helps...

Answer 2

One of the purposes of the subjunctive mood is to express doubt. By adding "no," after "no dudo que," you are removing the doubt from the expression, which follows the indicative mood.

Please find a list of other phrases that are normally subjunctive and include a sense of doubt below:

No creo que (I don't believe that)

No estoy seguro/a de que (I'm not sure that)

Es dudoso que (It's doubtful that)

No me parece que (It doesn't seem to me that)

No estoy convencido/a de que (I'm not convinced that)

Tal vez (Maybe)

Quizás (Perhaps)

Puede ser que (It may be that)

Es posible que no (It's possible that not)