"They do not eat the meal."
Translation:De spiser ikke måltidet.
Somewhere in the comments in an earlier module (I thought) I read that "ei" is a "charming" alternative to ikke, but "De spiser ei måltidet" is not accepted as a correct alternative here. As someone who needs all the charm they can possibly give off ;), when is it charming to use ei? Takk!
"Ei" is an alternative to "ikke", but it's a less common and largely dialect dependent one. People generally use one or the other, rather than mix "ei" in for added charm (I'd also say it's more quaint than charming in a general sense).
Unless you aim to speak a dialect that uses "ei" for "ikke", there is no reason for you to be using it outside of a few fixed expressions like "den gang ei", and, if you so wish, in some not-so-fixed expressions like "enten du vil eller ei" - where "ikke" would still be a very valid option.
However, you're right in saying that it should be accepted as an alternative here - and it is. :)