The word 加快 is formed by combining two independent characters, each contributing its core meaning to create a new, composite concept. The first character, 加 (jiā), carries the fundamental idea of "to add" or "increase". It is placed before the second character, 快 (kuài), which means "fast" or "speed". Their sequential combination does not merely list meanings but synthesizes them; the action of "adding" is directly applied to the state of "speed", thereby conceptually generating the meaning "to accelerate" or "to speed up". This formation is a direct semantic fusion where the first element acts upon the second.