knotty GRE

1.She met with a lot of knotty problems.

她碰上了许多棘手问题。

2.Even the professor couldn't clarify the knotty point.

甚至教授也无法解决这个棘手问题。

3.The system of the Unconstitutionality Review in our academic research of science of Law is a hot issue in China, which also is a knotty problem.

关于我国违宪审是当今法学界研究一个热点问题，也是令法学界比较头疼一个问题。

4.It has a website, but it still has to unlace the knotty problem facing all weeklies trying to manage themselves into an online future — what does a Web-based weekly look like?

商业周刊拥有一个网站，但是它仍需要解决当下面临难题，同时也是所有周刊杂志所面临问题，就是将来如何转变成为一家网上杂志，一家以网站为基础周刊看起来如何？