TASK DEFINITION: Given a sentence, generate a new sentence by performing small changes on the sentence. Here, make sure that the changes are semantically related and syntactically similar to the input. And the generated sentence should have high commonsense plausibility, that is to have reasonable probability of it being true.
PROBLEM: Expensive chocolate melts at mid temperature .

SOLUTION: Expensive chocolate melts at face temperature .

PROBLEM: You are likely to find a pin in a tree .

SOLUTION: You are likely to find a grape in a tree.

PROBLEM: You are likely to move a canvas in a museum .

SOLUTION:
You are likely to find a canvas in a driveway .