台湾籍旅美老师今天交给我们的句子是：
It wasn't until several centuries later that the heart became a symbol representing "love". But the problem was they didn't really know what the heart looked like.
直到几个世纪后，心形才变成象征爱的符号，但问题是当时他们根本还不知道心脏长什么样子。
学习重点：
1.several 一些；几个
several (pron.) 一些；几个
2.century 百年
century (n.) 百年
3.symbol 标志；象征
symbol (n.) 标志；象征
4.represent 作为…的代表 (或代理人)；作为…的代言人
represent (v.) 作为…的代表 (或代理人)；作为…的代言人
