Supposer may require the subjunctive, depending on how it's used. When making an assumption, no subjunctive: Par exemple… Je suppose que Liliane sait où il habite.

Is Je suppose que subjunctive?

When the French verb 'supposer' hypothesizes, it requires the subjunctive. When supposer ("to suppose" or "to assume") is used with a dependent clause beginning with que, the dependent clause may use a subjunctive verb, depending on how supposer is used. When it expresses an assumption, no: Je suppose qu'il le fait.

Does Je doute que take the subjunctive?

Je doute que is generally followed by the subjunctive because it expresses uncertainty.