Why does Naomi talk in masculine form to her daughters-in-law?
In Rus 1:8, Naomi is telling her two daughters-in-law that they should return to their homes.
וַתֹּ֤אמֶר נָעֳמִי֙ לִשְׁתֵּ֣י כַלֹּתֶ֔יהָ לֵ֣כְנָה שֹּׁ֔בְנָה אִשָּׁ֖ה לְבֵ֣ית אִמָּ֑הּ יעשה [יַ֣עַשׂ] יְהוָ֤ה עִמָּכֶם֙ חֶ֔סֶד כַּאֲשֶׁ֧ר עֲשִׂיתֶ֛ם עִם־הַמֵּתִ֖ים וְעִמָּדִֽי׃
But Naomi said to her two daughters-in-law, “Turn back, each of you to her mother’s house. May the LORD deal kindly with you, as you have dealt with the dead and with me!
How come she uses the masculine form of the bolded words instead of the feminine form (עִמָּכֶן and עֲשִׂיתֶ֛ן) when she is speaking to females?