1. 操场：double foul 双方犯规 | drill ground 操场 | equal a world record 平世界纪录
2. 练兵场：drill groove ==> 钻头构槽 | drill ground ==> 练兵场 | drill hammer ==> 冲击钻头
1. This drill also helps reduce ground contact time - creating a shorter, snappier stride and the feeling of " running over your feet ".
2. This drill was not the first amphibious landing exercise to be held between the Japan Ground Self Defense Force and the US Marines.
3. Rescue headquarters also said it might drill holes from the ground to accelerate the pumping process.