One way to create this obtuse angle is to lean back further.

形成这种钝角的方法之一是再向后倾斜一点

Are you being deliberately obtuse?

你是不是故意装傻？

I've been waiting for you to ask me the question yourself, and you're being obtuse and slow about it.

我一直在等你亲自问我这个问题，而你对此一直迟钝缓慢。

She can not possibly be so obtuse.

她不可能如此迟钝。

How can you be so obtuse?

你怎么会这么愚蠢？

The relevant obtuse Angle principle is proved.

并证明了相应的钝角原理。