insert two dashes where needed.\nthe aptly named petit pont a bridge in\nparis just 65 feet wide and 105…

Explanation:

To insert two dashes (an em dash, represented by two consecutive en dashes or a single em dash, but here we use two en dashes as per the instruction to insert two dashes) for parenthetical or explanatory information. The phrase "a bridge in Paris just 65 feet wide and 105 feet long" is an explanation of "Petit Pont", so we place two dashes around it. Also, the part "crosses the Seine at a point that has been used as a river crossing since the days of Julius Caesar" is a continuation, but the main insertion is around the descriptive phrase of the bridge. Wait, actually, the correct place is to set off the appositive "a bridge in Paris just 65 feet wide and 105 feet long" from "Petit Pont" and also maybe another? Wait, no, the sentence structure: "The aptly named Petit Pont——a bridge in Paris just 65 feet wide and 105 feet long——crosses the Seine at a point that has been used as a river crossing since the days of Julius Caesar." So we insert two dashes after "Petit Pont" and before "crosses" to set off the appositive clause.

Step1: Identify the appositive phrase

The phrase "a bridge in Paris just 65 feet wide and 105 feet long" is an appositive explaining "Petit Pont".

Step2: Insert two dashes

Place two dashes (--) after "Petit Pont" and before "crosses" to set off the appositive. So the sentence becomes: "The aptly named Petit Pont——a bridge in Paris just 65 feet wide and 105 feet long——crosses the Seine at a point that has been used as a river crossing since the days of Julius Caesar."

Answer:

The aptly named Petit Pont\boldsymbol{——}a bridge in Paris just 65 feet wide and 105 feet long\boldsymbol{——}crosses the Seine at a point that has been used as a river crossing since the days of Julius Caesar.