Examples:

• Well, i don't understand why you're being so nice to me.
• What i don't understand is why he invited us here.
• And i guess i don't understand why you're not.
• Yeah, i'm fine, it's just... i don't understand what you're doing.
• No disrespect, but i don't understand why you need us here.
• No, manager, there is a lot i don't understand.
• Trupti, i don't understand what you're saying to me.
• Look, i don't understand What's goin' on here.