LETTER SWAPPING X
Credit: GAMES Magazine - Feb. 2001
Stephen Sniderman

The title words to this puzzle, LETTER and SWAPPING can trade the L and W to make WETTER and SLAPPING. Each word in the left-hand column below can swap a single letter with one of the words in the right-hand column to create two new words. For example, you can switch the C in PROTECT with the S in DIREST to create PROTEST and DIRECT.

NOTE: There may be more than one way to pair certain words, but there is only one solution which uses all the words once and only once. 

1. PROTECT            SALVO
2. LEAD                   SERIAL
3. CAFE                    DIREST
4. RATIO                  BLUE      
5. TRIES                   GROWN             
6. DIRT                     DEAR               
7. AUCTION            MOPE

HINTS:
The swapped letters from the words in the left-hand column are:
1.T
2. A
3. F
4. R
5. E
6. R
7. A

Answers:

1. PROTEST...........DIRECT
2. LEWD.................GROAN
3. CARE..................DEAF
4. PATIO................ MORE
5. TRIOS................ SALVE
6. DIET................... BLUR
7. SUCTION...........AERIAL