Student: Given the sentence "A fireman climbing on charred ceiling beams of a burned out structure." is it true that "The fire fighter has his visor down."?.
Teacher: Let's think:

A fireman climbing on a charred ceiling beam need not necessarily be having his visor down. So the final answer is it is not possible to tell.
Student: Given the sentence "A fireman climbing on charred ceiling beams of a burned out structure." is it true that "The fire fighter has his visor down."?.
Teacher: Let's think:

user
A fireman climbing on a charred ceiling beam need not necessarily be having his visor down. So the final answer is it is not possible to tell.
assistant
Student: Given the sentence "A fireman climbing on charred ceiling beams of a burned out structure." is it true that "The fire fighter has his visor down."?.
Teacher: Let's think:

A fireman climbing on a charred ceiling beam need not necessarily be having his visor down. So the final answer is it is not possible to tell.