According to wikipedia:
A Gerund in Hebrew refers either to the verb's action noun, or to the part of the infinitive that follows the infinitival prefix (also called the infinitival construct).
My interpretation is it the noun that is formed from the verb root in each Binyan
Here are the patterns to form gerunds in Hebrew:
| Binyan | feeling | pattern | Notes | example root | example |
| פָּעָל | Root | פְּעִילָה | ספר | סְפִירָה | |
| פִּעֵّל | Intensive | פִּעוּל | Dagesh forte in ע position | ספר | סִפּוּר |
| הִפְּעִיל | Causative | הַפְעָלָה | Remember the dagesh qal in the ע position if needed after a shva | כתב | הַכְתָּבָה |
| הִתְפַּעֵّל | Reflexive | הִתְפַעְלוּת | dagesh forte in ע position. Remember the dagesh qal in the פ if needed after a shva | כתב | הִתְכַּתְּבוּת |
| נִפְעַל | Passive | הִפַּעְלוּת | dagesh in פ position | כנס | הִכַּנְסוּת |
Remember, not all roots formed the automatic gerund, so you need to look it up.