My battery commander（连长） and I were interviewing candidates for a position as reconnaissance（侦测，勘探） sergeant in our artillery（火炮，大炮） unit. The selected soldier needed to have keen eyesight, plus the ability to react quickly. During one interview, the commander pointed to a hill about a mile away and asked a young sergeant, "Can you see that hill over there?"
"Yes, sir." he replied.
"Can you see the radio antenna（天线，触角） on that hill?" Again, the soldier said that he could. "Well, then," the commander went on, "Can you see that bird sitting on the antenna?"
The sergeant leaned forward and squinted（斜视） . "No, sir," he said, "but I can hear it is singing."
He got the job.