What do the following words have in common?

1. ATE

2. BIT

3. ALLY

4. DEAL

5. CHARD

HINT:

Each word can be preceded by the same two letters.

Answer:

 

Each word can be changed into a new one by preceding it with the letters OR:

 

1. ORATE

2. ORBIT 

3. ORALLY

4. ORDEAL

5. ORCHARD