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: You can use a roof to provide shelter.

SOLUTION: You can heat a roof to provide concrete .

PROBLEM: You are delighted to build a creature around in the forest .

SOLUTION: You are likely to chance a creature around in the forest .

PROBLEM: The effect of taking a phone call is to apply to someone .

SOLUTION:
The effect of establishing a phone call is to talk to someone .