How do you say in french 'as much as you can' 'autant que tu peut' or 'autant que tu puisse' autant que requires the following verb in the subjonctive or not?

Answer 1

Autant que does not require a subjunctive after it. It is merely used as 'as much as'.

Ex1: (using present and not subjunctive) Serre la vis autant que tu peux (tighten the screw as much as you can) ;

Ex2: (using que + subjunctive) Je ne crois pas que tu puisses le serrer davantage (I don't believe you could tighten it any more) ;

Ex3: (similar meaning, using present and no subjunctive) je ne crois pas que tu peux le faire : I don't believe you can do it.

However, some fixed expressions use the subjunctive, as 'autant que je sache, ...' (as far as I know, ...).

When in doubt, remember that French schoolchildren are taught to use the simplest alternative - here the present vs the subjunctive.