This was the first time that Joyce had spoken French, and Eugenia was so surprised she couldn't help showing it, and asked her why she had never said anything before in that language.

Joyce told her that her teacher never allowed her to mix the languages.

She said it was in bad taste to do so in speaking to people who only understood one; that it seemed affected, or as if the person wanted to show off how much she knew.
Then that made Eugenia mad, and she asked her in a spiteful way if it was a public school teacher that told her that, and said she didn't know that they taught French out West.

Joyce said yes, that they did, but that of course a year abroad was quite a help, and that before she left France they told her that her accent was quite Parisian.
That took the wind out of Eugenia's sails.

She did not know that Joyce had been abroad.