Radical 山
6 strokes
歲
mountain 山 (110) + evening 夕 (69a) = years old 岁
[三十岁 (3, 4) sānshísuì 30 years old]

(A mother is scolding her young son) “You must never be out by yourself on the mountain in the evening until you’re 16 years old.” / The ghostly dwarf whose job is to protect climbers on the mountain (not young boys) is angry too, as he hands the boy back to his mother. “It’s not safe to be on the mountain alone at your age,” he tells him.