When I opened the door, I found my father sitting in his chair, completely ______ in the humorous stories he was reading.
If we the other road, we might have arrived here in time for the meeting. (2010 .陕西)
If you to see Mary, what would you tell her?
If the sea to rise 50 feet, India would become an island.
If you hadn’t gone with Tom to the party last night, .
I it to him if he didn’t understand.