YOU SAID:

A few pencils short of a pencil case

INTO JAPANESE

筆箱に足りない数本の鉛筆

BACK INTO ENGLISH

A few pencils not enough in the pencil case

INTO JAPANESE

筆箱に足りない数の鉛筆

BACK INTO ENGLISH

Insufficient number of pencils in the pencil case

INTO JAPANESE

筆箱の鉛筆の数が足りない

BACK INTO ENGLISH

Not enough pencils in the pencil case

INTO JAPANESE

筆箱に鉛筆が足りない

BACK INTO ENGLISH

Not enough pencils in the pencil case