The past tense of put a stumbling block in the way of is also put a stumbling block in the way of.

The third-person singular simple present indicative form of put a stumbling block in the way of is puts a stumbling block in the way of.

The present participle of put a stumbling block in the way of is putting a stumbling block in the way of.

The past participle of put a stumbling block in the way of is put a stumbling block in the way of.