英语中，介词如'in'和'at'用来表示名词与其他词之间的关系。

In English, ___prepositions like 'in' and 'at' show relationships between nouns and other words.

画作在墙上的恰当布置可以提升房间的整体美感。

Proper ___placement of paintings on the wall can enhance the overall beauty of the room.