If I have two yahoo email addresses, can I combine them so I only have to login to one and can view both?

Sorry.... not possible. You have to open them separatly. Log onto one... read your emails, etc., then log off, and log on to the other account. They can't be combined. The only way to open them at the same time would be to open one account with one browser, and the other with a 2nd browser, which doesn't seem worth the trouble.

If I have two yahoo email addresses, can I combine them so I only have to login to one and can view both?
Have you tried to do a mail merge. You can merge both accounts together. This should allow you to read both accounts at the same time because, they will be merged together. Try it to see if this will solve your problem. Hope this work for you.