所长

(suǒcháng) what one is good at; one's strong point; one's forte

♦ 有~必有所短。 Where you are strong on one thing, you are weak on another.

所长
(suǒzhǎng) the head of an office, institute, etc.

♦ 研究所~ the director of a research institute

♦ 托儿所~ the head of a nursery