The pattern with "Knight takes e7 check" seems to be common when talking about zwischenzug. Have a look at the following problem:
Find more examples of zwischenzug in my latest blog post: http://chesstrainerapp.blogspot.fr/2014/02/zwischenzug-say-it-again.html
Here's a nice continuation in puzzle form. Black has just played Na5, threatening your queen and bishop. Can you sidestep this threat and find the winning line?