A week later two more visitors called,serious-looking men in
A week later two more visitors called,serious-looking men in identical dark blue raincoats,wearing identical dark blue hats.
请问
1)serious-looking 是什么样的词汇结构?
2)serious-looking men in identical dark blue raincoats,是什么成份?
3)为什么wearing要-ing,wearing identical dark blue hats这是个什么结构作什么成份?