Shemot 15:24

וילנו AND THEY MURMURED — This is a Niphal form, and similarly the Targum is a Niphal form: ואתרעמו (the Ithpael form in Aramaic corresponds to the Hebrew Niphal). And such is the way in which the expression denoting murmuring (from root לון) is employed: to refer back the matter (the action of murmuring) to the person (the subject of the verb); thus one says מתלונן and מתרועם and one does not say לונן and רועם. So, too, the Frenchman says “decomplaisant se” in old French, where it turns back the matter (the action) to himself (the subject) by saying, “se”, English himself.

וַיִּלֹּ֧נוּ הָעָ֛ם עַל־מֹשֶׁ֥ה לֵּאמֹ֖ר מַה־נִּשְׁתֶּֽה׃

And the people murmured against Moshe, saying, What shall we drink?