[General] What is/was the strangest thing you've ever seen?

[beachboy]

What is the strangest thing you've ever seen?
What was the strangest thing you've ever seen?

Are both of the questions above right? What about the answer? Is or was?

 

[probus]

Both is and was are equally acceptable in the question and in the reply. As to which is more common, I defer to somebody who is better than me at n-grams.

 

[Rover_KE]

More common than either of those is 'What's the strangest thing you've ever seen?'

 

[emsr2d2]

I'd use "is" with "you have ever seen" and "was" with "you had ever seen". They would be used in different contexts, of course.

 

[Tdol]

Both is and was are equally acceptable in the question and in the reply. As to which is more common, I defer to somebody who is better than me at n-grams.

It only works with five-word phrases. COCA has a similar limit unless you have a premium account, though it's probably not big enough for a decent comparison of such long phrases.