adj.[生](细胞或微生物的培养)生活期有限的
动词span的过去式及过去分词形式.
A bridge spanned the stream. 一座桥横跨这条河流。
Emily is a Londoner born and bred and, for a woman some years past the allotted span, of a truly remarkable vigour and alertness. 埃米莉生在伦敦长在伦敦,虽已年逾古稀,但实在令人惊讶的是,她仍精力充沛,耳聪目明。