The basic difficulty is suggested by the following trees representing the phrase structures of the sentences:

The transcripts underline a basic difficulty in the prosecution's case against the sheik.

It was this technique that formed the basic difficulty of manufacture.

The basic difficulty behind these choices is an old one: how should the perpetrator commemorate or simply remember the crime?

"We probably underestimated the basic difficulty of the institutional transformation of Russia," one senior official said.

One basic difficulty with the piece is how to coordinate what's happening on screen with the live action on stage.

The reactions demonstrate a basic difficulty with mechanical reproduction of music: there is a subjective element involved in determining if it works.

A basic difficulty of interpretation centers upon what the poet means by 'immortality.'

The basic difficulty derives from the cost of the technology.

And there was the basic difficulty for the refugees of finding new identities and using a new language.