Ahh, grammar & such! In that case, I'd actually say what you probably want is more input, and not output. Your brain should intuitively know what the correct tense and sentence structure is, and the only way it can learn that is by consuming VAST amounts of content in that language.
Then with a little attention, you'll start using the correct tenses and sentence structures as matter of course :)
Then with a little attention, you'll start using the correct tenses and sentence structures as matter of course :)