从坦克的观察窗商只能看到蓝天白云而无法看到路面上的情况。
1·The paper develops embrasure plugging a-gent(FD-2) with high strength according to the present problem that cement plugs embrasure.
针对目前水泥浆封堵炮眼存在的问题，研制开发了不留塞高强度炮眼封堵剂FD-2。
2·The window was an embrasure in an enormously thick wall.
窗户是个炮眼，墙壁异乎寻常的厚。