The following is a group letters,but two are missing.Can you work them out?

问题描述:

The following is a group letters,but two are missing.Can you work them out?
J F M A M J J A __ __ N D

S O
英文十二个月份的首字母排列,刚好排到九月和十月
解题时首先审视这串字母,通过前面字母判断不是一个单词(查字典
然后我查了一下,一共十二个字母,还挺长的,就想到十二月份了.
哈哈