in one,s opinion请问opinion有复数么?

in their opinion 中的 opinion有复数么? 关于in one’s opinion in one's opinion=? in one’s opinion是什么意思? in one's opinion中的opinion加不加s "in my opinion"中的opinion可以加s吗 为什么in their opinion中的opinion不加s? in my opinion 中opinion要加s吗 in their opinion opinion后是否加s in one's book 和 in one s opinion 的区别 可以说“agree with one's opinion”吗? opinion