1.  Chimpanzees have been observed to indulge in mobbing in certain unusual cases.

2.  In some unusual cases one is willing to apply the term when only one of these conditions obtains.

3.  It was a very unusual case.

4.  Yes, there are unusual cases.

5.  Mr. Hitchens said you have solved some very unusual cases.

6.  We need more guidance on how to handle these unusual cases.

7.  An unusual case of bilateral ureteric obstruction and hydronephrosis due to pancreatic pseudocyst formation, after an episode of acute pancreatitis is reported.

8.  An unusual case on the books involves a journalist in France.

9.  A Manhattan man will go to jail for helping his wife commit suicide, after he pleaded guilty Friday to a reduced charge in the unusual case.

10.  Accepting an appeal from the federal government, the court agreed to decide an unusual case involving the intersection of the Freedom of Information Act and foreign policy.