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: If you want to recognize a computer then you should appropriate an application program .

SOLUTION: If you want to use a computer then you should mail an application program .

PROBLEM: A credit card is disposed of plastic .

SOLUTION: A credit card is handmade of plastic .

PROBLEM: Your goal could be to compute the distance of some numbers .

SOLUTION:
Your goal could be to compute the median of some numbers .