Input (grade 10): The line of march was now stretched out perilously long â "estimates are that it surpassed 15 km (9 miles), and was perhaps as long as 20 km (12 miles).
Output (grade 10): The line of march was dangerously stretched out â "estimates are that it was more than 15 km (9 miles), and was perhaps as long as 20 km (12 miles).