The past tense of cross a bridge when one comes to it is crossed a bridge when one comes to it.

The third-person singular simple present indicative form of cross a bridge when one comes to it is crosses a bridge when one comes to it.

The present participle of cross a bridge when one comes to it is crossing a bridge when one comes to it.

The past participle of cross a bridge when one comes to it is crossed a bridge when one comes to it.