Tā de shǒuzhǐ xiānshòu xiūcháng, hěn shìhé tán gāngqín.
His fingers are slender and long - perfect for playing the piano.
Tips
usage
Positive and aesthetic - 'slender / delicate,' not 'skinny.' Pair words: 苗条 (slim and graceful) is similar; 瘦 on its own is neutral; 骨瘦如柴 ('bones thin as kindling') is negative.
memory
纤 carries the sense of 'fine, delicate, fiber-thin' (same character as in 纤维, fiber). Adding 瘦 (thin) gives that elegant willowy thinness - not gaunt.
