关于CFA 2级，periodic vs. perpetual inventory system的问题 system, 如何

xjleric

教材上有一段没弄明白，

In the case of FIFO and specific identification, ending inventory values and COGS are the same whether a periodic or perpetual system is used. Conversely, there can be significant diferences in inventory values and COGS when using weighted average cost and LIFO basd on the system used.

这段话如何理解啊？谢谢大家解答！