From the song: "Cheerilee is sweet and kind... she's the best teacher we could fin^D^D^Dhope for."
"That's an apple tree." "*Is* it!"
"OH COME ON!"
"We thought the two of you would be perfect together! To test it. Together."
"We just need to keep them apart for an hour? We can do that in a second!"
"Girls? Why do I look like I'm getting married at the bottom of a pit?"
I also really liked Kif as the diamond-seller (with the amazingly horrible elements of tackiness diamond on display) and the way the CMCs got Apple Bloom not to get trapped in the pit without actually warning Big Mac. And Mrs. Cake's nervous glances were as amusing as always.
Not to mention Cheerilee, Bane of Doors.
At any rate, I really really liked this one -- it's one of the best this season. And it was using a premise I expected to hate a lot.