Answers

1. CAT-COT-DOT-DOG or CAT-COT-COG-DOG.

2. BOY-BAY-MAY-MAN or BOY-BAY-BAN-MAN.

3. HARD-CARD-CART-CAST-EAST-EASY.

4. EAST-PAST-PEST-WEST or EAST-LAST-LEST-WEST.

5. ONE-OWE-EWE-EYE-DYE-DOE-TOE-TOO-TWO.

6. BREAD-BREAK-BLEAK-BLEAT-BLEST-BLAST-BOAST-TOAST.

7. SICK-SILK-SILL-WILL-WELL.

8. RICH-RICK-ROCK-ROOK-BOOK-BOOR-POOR.

9. GRASS-CRASS-CRESS-TRESS-TREES-TREED-GREED-GREEN.

10. TREE-FREE-FLEE-FLED-FEED-WEED-WELD-WOLD-WOOD or TREE-FREE-FLEE-FLED-FEED-FEND-FOND-FOOD-WOOD.

11. HATE-HAVE-LAVE-LOVE or HATE-HAVE-HOVE-LOVE.

12. BLACK-BLANK-BLINK-CLINK-CHINK-CHINE-WHINE-WHITE

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