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: A pencil is discarded for writing .

SOLUTION: A theme is used for b .

PROBLEM: The effect of going to a party is you travel drunk .

SOLUTION: The effect of going to a party is you disappear drunk .

PROBLEM: You are likely to find a lamb in a city zoo .

SOLUTION:
You are bizarre to find a monkey in a city zoo .