This detective story is boring.

这个侦探故事很没意思。

It's like a detective story.

这就像是一个侦探故事。

I want a detective story please.

请借我一本侦探小说。

I want a detective story, please.

我想要一本侦探书。

It's a very serious detective story.

这是一部非常严肃的侦探小说。