Student: Given the sentence "Two men are attaching a sign to a standing log." is it true that "Two men were hammering nails into the fence."?.
Teacher: Let's think:

A sign can be attached without hammering nails. A standing log isn't always part of a fence. So the final answer is it is not possible to tell.
Student: Given the sentence "Two men are attaching a sign to a standing log." is it true that "Two men were hammering nails into the fence."?.
Teacher: Let's think:

user
A sign can be attached without hammering nails. A standing log isn't always part of a fence. So the final answer is it is not possible to tell.
assistant
Student: Given the sentence "Two men are attaching a sign to a standing log." is it true that "Two men were hammering nails into the fence."?.
Teacher: Let's think:

A sign can be attached without hammering nails. A standing log isn't always part of a fence. So the final answer is it is not possible to tell.