External doors should be of robust construction.

【construction】外门应该是结构坚固的。

Simultaneously with the conclusion of Stephen's remark, the sound of the closing of an external door in their immediate neighbourhood reached Elfride's ears. It came from the further side of the wing containing the illuminated room.

就在史蒂芬的话音落下的同时，埃尔弗莱德的耳朵里传来了紧邻的一扇外门关上的声音。它来自包含照明房间的机翼的另一侧。