문제 내용: 밑줄 친 부분 중 어법상 옳지 않은 것은?
  Each year, more than 270,000 pedestrians ① lose their lives on the world's roads. Many leave their homes as they would on any given day never ② to return. Globally, pedestrians constitute 22% of all road traffic fatalities, and in some countries this proportion is 3 as high as two thirds of all road traffic deaths. Millions of pedestrians are non-fatally injuring some of whom are left with permanent disabilities. These incidents cause much suffering and grief as well as economic hardship.
선택지 1: ① lose their lives
선택지 2: ② to return
선택지 3: 3 as high as
선택지 4: non-fatally injuring