How do you say I will study harder in french?

There are a few ways to say "I will study harder" in French, depending on the level of formality and nuance you want to express. Here are a few options:

Formal:

* J'étudierai plus sérieusement. (I will study more seriously.)

* Je travaillerai davantage. (I will work harder.)

* Je m'appliquerai davantage à mes études. (I will apply myself more to my studies.)

Informal:

* Je vais bosser plus. (I'm going to work harder.)

* Je vais me donner plus de mal. (I'm going to put in more effort.)

* Je vais me concentrer plus. (I'm going to focus more.)

Other variations:

* Je vais redoubler d'efforts. (I will redouble my efforts.)

* Je vais faire de mon mieux pour étudier plus. (I will do my best to study more.)

The best option for you will depend on the context and your relationship with the person you are speaking to.