2. S

3. 1° FOR MOST NOUNS, JUST ADD -S
SINGULAR PLURAL
RABBIT RABBITS
HAND HANDS

4. SINGULAR PLURAL
BOX BOX ES
PITCH PITCH ES
DISH DISH ES
GLASS GLASS ES
BUZZ BUZZ ES
POTATO POTATO ES

5. SINGULAR PLURAL
SPY Spi ES
POPPY POPPi ES
PENNY PENNi ES

6. SINGULAR PLURAL
WiFE WIVE S
KNiFE KNIVE S
LiFE LIVE S

7. SINGULAR PLURAL
WOLF WOLV ES
THIEF THIEV ES
HALF HALV ES