You can do this with message filters. Go to the menu Tools > Message Filters or click on the Hamburger button and select Message Filters > Message Filters. Here you can create a filter that applies to incoming messages that meet certain criteteria, such as Subject containing a certain string and define actions to apply to those messages, such as forward, mark read and store the message in a folder. Note that the default forward method is chosen, e.g. forward inline or forward as attachment. You can change the default method with the menu Tools > Options > Composition > General > Forward messages as... If you want to forward in a specific format, no matter what setting uyou have configured here, you can install my Forward extension, which adds two filter actions: Forward inline and Forward as attachment.

Thank you Onno, that works!

Do you also know if/how to forward only part of the body? for example, split the whole message into multiple messages and then send them out.

The reason I am asking is I want to forward some emails to my SMS so I can receive them as text message on my cell, however, there are character limit for the SMS.

Thanks lots.

Besides, gmail automatically categorizes emails into Primary, Social, Promotion and Forum, is there a way to do the same categorization in Thunderbird so that different emails go to different folders in Thunderbird?

Thanks.