他擅长蛋糕装饰。

He's good at cake ___decoration.

我们在树上挂上了色彩缤纷的圣诞装饰品。

We hung colourful Christmas ___decorations on the tree.

她参加了一个课程学习如何制作圣诞装饰品。

She joined a course to learn how to make Christmas ___decorations.