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: To open a locked door you usually need to have a buddy .

SOLUTION: To open a locked door you usually need to have a key.

PROBLEM: You tell a lie because you think no one will stake out .

SOLUTION: You tell a lie because you think no one will fill out .

PROBLEM: You are likely to find a baby in a motel .

SOLUTION:
You are likely to find a donation in a publication .