Yes, I think he did murder his wife because he seems suspicious.
2) Why do you think the Indian figures on the table are disappearing?
I think they are disappearing because the murderer is taking them after he kills someone.
3) Do you think Anthony Marston and Mrs. Rogers were murdered or committed suicide?
I think they were murdered because it's more likely then two suicides in a row.
4) Why do you think they couldn't find the murderer on the island?
I think the murderer can't be found on the island because he is one of the guests.
5)What do you think will happen next?
I think someone else will be murdered following the Indian poem.