Yesterday in class, we practiced agreeing and disagreeing politely.
Here's a video that explains how to sound more polite when disagreeing with someone.
Video Link: https://youtu.be/NFzDSKsP54Q
Here is a video with common phrases used for agreement and disagreement.
Video Link: https://youtu.be/CzA0tjRgDZA
Want to learn more phrases? Click this link: http://uki.vdu.lt/wp-content/uploads/sinergija/EN/etika/etika1/Agreeing_and_Disagreeing.pdf