"Vous ne réfléchissiez pas assez avant de jouer."
Translation:You did not use to think enough before playing.
It is certainly not natural English but at least you can understand that the French sentence is about a past repeated action.
"You did not think enough before playing" can be about a one-time event, which would back-translate to a passé composé: Tu n'as pas assez réfléchi avant de jouer.
It's impossible to split an infinitive since infinitives are one word -- "to" is an adjunct for clarity, since Middle English had lost a lot of its inflections and it was no longer easy to tell the difference between verb forms. The rule against it started with the American "linguist" John Comly in 1803 as a matter of preference, so it's an arbitrary rule.
horrible, awkward English. I'm not certain that it is grammatically correct. I meant to report it but got distracted and forgot. I'll try to remember if I see it again.
"You do not think enough before playing" is probably the best translation for this, and it is how I would translate it were I translating a book or article from French to English. If one really wanted to keep the sense of the imperfect, then one could use "You were not thinking enough before you played" or, taking some poetic licence, "you were not in the habit of sufficient reflection before playtime" or something like that.
If I hired someone to translate "Vous ne réfléchissiez pas assez avant de jouer" and he wrote "You did not use to think enough before playing" I think I would never hire that person to translate anything again.
Indeed, the "best" translation you suggest is not acceptable because of the tense. The past imperfect tense has several, alternative translations depending on meaning, and your translation(s) in English must demonstrate that you have properly understood what the French sentence meant, as accurately as possible, and even if it is not the way you would say it in your daily life.
- a past, on-going action or state: you were not thinking (accepted)
- a past habit/repeated action or state: you used not to think; you did not use to think; you would not think (accepted).
We are well aware that some of those technically possible translations are awkward, but they remain faithful to the French meaning, and you could safely pick "you were not thinking", although the meaning is much more probably that of a repeated past action.
It's either "used to" or "did not use to" per the following: As reported by the NOAD in a note about the usage of used:
There is sometimes confusion over whether to use the form used to or use to, which has arisen largely because the pronunciation is the same in both cases. Except in negatives and questions, the correct form is used to: we used to go to the movies all the time (not we use to go to the movies). However, in negatives and questions using the auxiliary verb do, the correct form is use to, because the form of the verb required is the infinitive: I didn't use to like mushrooms (not I didn't used to like mushrooms).
The problem here people is that you are all using the word "used" as in "You used not think enough before playing". Duo is not using the word "used" here, it is using the word "USE" which in my book is just pain bad english. The above sentence should be " You did not used to think enough before playing" (or suitable variations thereof)