复数是把y变为i，加es，复数形式是dictionaries，例如：

1.English textbooks and dictionaries are on sale everywhere英语教材和词典到处都有卖的。

2.Dictionaries are indispensable in English study.学英语，词典是少不得的。

3.There are a lot of dictionaries in the reading room. You will find them very handy if you go there to study.阅览室词典多，在那儿学习很方便。