The term 'CONCENTRATE ON' can be broken down into four crossword solutions: FOCUS (5 letters), ESSENCE (7 letters), STUDY (5 letters), and FIXATE (6 letters). Focusing is the act of directing one's attention or concentration on a particular object or task. The ESSENCE of something is its most important or essential part. Studying involves the careful observation and analysis of a subject. Fixating is to FOCUS one's attention on something obsessively. Therefore, the phrase 'CONCENTRATE ON' can be interpreted as directing one's attention to a particular object or task, understanding its most important aspects, and studying it carefully and obsessively.