Can Zenitsu only use one form?

Can Zenitsu only use one form? Zenitsu has learned and mastered only the first form of Thunder Breathing, although he knows a total of three variations of this form. This was the basic form he had to learn, but he never mastered the others, although he could because he knows that basic form.

Zenitsu has learned and mastered only the first form of Thunder Breathing, although he knows a total of three variations of this form. This was the basic form he had to learn, but he never mastered the others, although he could because he knows that basic form.