The word 力所能及 is formed by sequentially combining the characters 力 (lì, meaning "strength" or "power"), 所 (suǒ, a particle here indicating "that which"), 能 (néng, meaning "can" or "able"), and 及 (jí, meaning "reach" or "attain"). This creates a literal construction meaning "that which strength can reach", which directly conveys the idea of something being within the scope of one's capabilities or power.