| A | B |
a pencil,  | a pencil,  |
pencils,  | pencils,  |
a pen,  | a pen,  |
pens,  | pens,  |
a ruler,  | a ruler,  |
rulers,  | rulers,  |
a marker,  | a marker,  |
markers,  | markers,  |
a book,  | a book,  |
books,  | books,  |
a pencil sharpener,  | a pencil sharpener,  |
pencil sharpeners,  | pencil sharpeners,  |
a crayon,  | a crayon,  |
crayons,  | crayons,  |
a CD,  | a CD,  |
CDs,  | CDs,  |
an eraser,  | an eraser,  |
erasers,  | erasers,  |
|