For example, apron really used to be napron. "A napron" got wrongly understood as "an apron" And the word alcohol has incorporated the article "al" into the word.
Not relevant for this quiz but still interesting and relevant to the previous point is when things got pluralised more than once. Where the plural was taken to be the singular form. One that might be forming currently is with dice, many people think dice is also the word for a single die (which is the actual singular). They say "throw the dice" when only referring to one. Like the singular and plural of deer is deer.
Also tried shellac for shall ay, and deus and dice for die us, (I think dice should be accepted actuallly) and coaxing for cocks un. All very close.
Still only missed 4 though. Really didnt see chalet, and tried chutspah with an s instead of z (and many other variations, it is a tough, one, because yiddish gets "translated" (not really, just altered) differently per country. and the other 3 lowest I hadnt heard of, Ennui rang a bell before I even saw it, and seeing it I think ow yea that was the word in my head, but I have no idea what it is.