Your sentence is perfect: "When he arrived, his wife was asleep." You can also say: "When he arrived, his wife was sleeping." To my British ears, this one sounds a little more literary, a bit more formal. But they are both correct. You can't say "When he arrived, his wife was slept". This is grammatically wrong. You CAN say "When he arrived, his wife slept." It's a bit weird though. It sounds like the moment he came back through the door, she fell asleep immediately, at that moment. If you want to say that she was asleep BEFORE he got home, you need to say, "When he arrived, his wife was asleep" or "When he arrived, his wife was sleeping". Hope that helps!

I know it's confusing

Yea, my question is!! was what's the better way to say this sentence.... when he arrived his wife was asleep instead of saying that, do you think I can say his wife was slept or sleeping what do you think?

What do you need help with?