The Subjunctivisor!
Does être sûr require the subjunctive?
Être sûr may require the subjunctive, depending on whether it is used affirmatively, negatively, or interrogatively:
Par exemple…
Je suis sûr que Viviane le sait.
I’m sure Viviane knows.Je ne suis pas sûr que Viviane le sache.
I’m not sure Viviane knows.Es-tu sûr que Viviane le sache ?
Are you sure Viviane knows?
Related: Does il est / c’est sûr que need the subjunctive?
The Subjunctivisor! | Subjunctive lesson
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