The answers to the clues below will have something in common.

1. Certain fruit
2. Certain U.S. state
3. Certain Round Table Knight
4. Certain capital city of South America
5. Certain headwear
6. Certain Sahara Desert sight
7. Certain watercraft
8. Certain waterway
9. Certain language of Barcelona
10. Certain month in the Islamic calendar

Answers:

1. BANANAS
2. ALABAMA
3. GALAHAD
4. CARACAS 
5. PANAMA HAT
6. CARAVAN
7. CATAMARAN
8. PANAMA CANAL
9. CATALAN
10. RAMADAN

All the answer words have alternating A's - and no other vowels.

Credit:
NPR Weekend Edition Sunday Puzzle
January 16, 2010
Will Shortz