GMAT
The recent surge in the number of airplane flights has clogged the nation's air-traffic control system, to lead to an increase of 55 percent in delays at airports, and prompted fears among some officials that safety is being compromised.
The recent surge in the number of airplane flights has clogged the nation's air-traffic control system, leading to a 55 percent increase in delays at airports and prompting fears among some officials that safety is being compromised.
题目基本信息