"When do those people eat?"

Translation: वे लोग कब खाते हैं?

[Tanya209986]

What is the difference between 'kab' and 'kabhi'?

[apubhadaram]

कब makes a question. Just like क्या or कैनसी. It means "when". For example: तुम कब पढ़ते हो? "When do you read/study?"

कभी determines the frequency of the occurence of an event. It has different forms/variations. For ex:
कभी कभी (sometimes) - मैं कभी-कभी सड़क पर दौड़ता हूं "I sometimes run on the road"
कभी नहीं (never) - मैं सुबह कभी नहीं सोता "I never sleep in the morning"

I hope it helps :D