When I saw last time, that pen is in the shop, it may or may not be there now. = nenu last time chuusinappudu, aa pen shop lo undi, ipudu adi undo ledo! ( నేను last time చూసినప్పుడు ఆ pen shop లో ఉంది, ఇప్పుడు అది ఉందో లేదో )

undi is feminine gender. she IS there. aame akkads UNDI. there IS a bus = akkada oka bus UNDI. this flower IS beautiful= ee pushpam Andamga UNDI.

undi means it is present for example there is book on the table undo means whether it is present or not for example whether the book is present or not