however conj. 然而；可是【语义相当于whereas, while, nevertheless, but, yet】

【可以位于句首，句中或句末】

However, the vote did not end the conflict between Congress and the White House over the future of the South.

I would never wish to duplicate that, however, I think there's a take-away.

我不会再来一次，但是，我想人们应该从中得到些什么。

It turned out wrong,however.

however adv.无论如何；不管怎样【语义相当于anyway, at all events】，可以引导状语从句，置于句首或句中。

However you praise the film, I just feel it so-so.

不管你怎么夸耀那部影片，可我觉得它不过如此。

We will try our best to finish the work on time however hard it is.

不管这项工作有多难，我们都要尽最大努力按时完成它。

【补充】引导状语从句时，however一般可以替换为 【no matter how+形容词或副词】结构。

We will try our best to finish the work on time however hard it is.

=We will try our best to finish the work on time 【no matter how hard it is】.

由此可见，你所问的句子中，however 是连词，位置可以灵活变换。要注意的是，位于句首，后面要加逗号；谓语句中，前后都要加逗号；位于句末，前面要加逗号。

祝你进步，时时开心！O(∩_∩)O~~