1.  Even though this year has been a difficult one, I have never regretted my Decision.

2.  The belief that hierarchical organizational structure makes for good business is a difficult one to give up.

3.  This is perhaps the most difficult one and brings up a number of fundamental contradictions.

4.  Any experience can teach and strengthen you, but particularly the more difficult ones.

5.  Now there is a difficult one.

6.  The question of the assessment of practical training was a difficult one.

7.  Given that computer procurement is also completely devolved upon departments, and even sub-sections of departments, the issue of standards becomes a difficult one.

8.  This problem of non-conforming uses is an extremely difficult one.

9.  The third feature of the Constitution that I have listed -- that the United Kingdom is a unitary state -- is a less difficult one to comprehend.