单项选择题
A. Remember: safety first. B. Mind. Safe the first. C. Think of it. Safety is one. D. Think of it. Safety first.
A. Watch your feet! Get hold on the rails. B. Watch your step! Get hold of the rails. C. Watch your step! Get hold to the rails. D. Mind your head! Get hold of the rails.
A. The captain is giving orders. B. The pilot is giving orders. C. The quartermaster is giving orders. D. The pilot is given orders.