What's missing letter? BO_K
BOOK
What's this?
pen
What's missing letter? PENC_L
PENCIL
What's this?
pencil
What's this?
ruler
What's this?
book
What's missing letter? RU_ER
RULER
What's missing letter? R_BBER
RUBBER
What's this?
rubber
What's missing letter? P_N
PEN