They could not move their heavy mortars over the swampy ground.

他无法把重型迫击移过那片沼泽。

Pvt.Chalmers Davis, a mortarman, found an observation post on top of a wrecked house.

迫击手，列兵查尔姆斯·戴维斯在一所炸毁房屋顶上兵观测阵。

The front line belong to the men who worked there—rifle-men and machine gunners, mortarman, forward artillery observers, communications men, and medics.

前沿带为作业于此所掌握——步枪兵、机枪兵、迫击兵、火校射兵、通讯兵，以及救护兵。