The plane trees lining the main street are leafing out. 街两旁梧桐树已冒芽。
The leaves turn yellow in autumn. 黄。
leafing [ noun ] (botany) the process of forming leaves <noun.process>
Leaf \Leaf\, Leaf out \Leaf out\(l[=e]f), v. i. [imp. & p. p. {Leafed} (l[=e]ft); p. pr. & vb. n. {Leafing}.] To shoot out leaves; to produce leaves; to leave; as, the trees leaf in May. --Sir T. Browne.