小测验：选择正确的单词

1. The perimeter of the airfield is protected by guard - dogs.
   机场外的环形防卫圈由警犬保卫着。
2. The plane limped toward the airfield.
   那架飞机艰难地朝机场飞去。
3. The airfield is bounded by woods on all sides.
   飞机场的四周都是树林.
4. The aeroplanes landed on the airfield.
   飞机在机场降落。
5. We must prolong the runway of the airfield.
   我们必须加长机场跑道。

　1个名词解释