The past tense of cut the ground from under someone's feet is also cut the ground from under someone's feet.

The third-person singular simple present indicative form of cut the ground from under someone's feet is cuts the ground from under someone's feet.

The present participle of cut the ground from under someone's feet is cutting the ground from under someone's feet.

The past participle of cut the ground from under someone's feet is cut the ground from under someone's feet.