This is the 7601st most frequent Chinese word.
走私
"走私" means "smuggling."
The word "走私" in this sentence is used as a noun, referring to smuggling activities.
他因为参与走私活动被捕了。
He was arrested for participating in smuggling activities.
Here, "走私" is combined with "行为" to signify the act or conduct of smuggling.
政府正在采取措施打击走私行为。
The government is taking measures to combat smuggling activities.
In this context, "走私" modifies "商品," describing the goods that are smuggled.