Please consider the following exercise:
The sky is so red, it looks as it if (be) ... on fire.
What verb do must I put at that empty place please? And why?
And what about if the exercise were this:
The sky is so red, it looks as if it (be) ... on fire.
This is an exercise from book English Grammar Digest by Trudy Aronson. And that book has written first version! I used had been. Is it correct please?