The term 'USE A SIEVE ON' can be solved by the word 'SIFT', which is a four-letter word. Sifting is a process used to separate smaller particles from larger ones, such as flour or sugar. It is done by passing the material through a sieve, which is a device with small holes that allow the smaller particles to pass through while the larger ones remain. This process is often used in baking to ensure that the ingredients are properly mixed and evenly distributed.