同根派生 sap wood相关词英汉例句Sapwood is the lighter colored wood growing from inside the bark to the heartwood.边材色泽较浅，是从树皮到新材之间的木质部分。Heartwood is the mature wood, which is often darker, extending from the sapwood to the pith.心材通常是成熟的木材部分，通常色泽较暗，范围从边材一直到髓心。sap wood更多例句