Since Tamil is a relatively rare language. It'd help, if you:
- posted a short ePub excerpt
- clearly indicated in a screen capture where unwanted line-breaks occur and where they should occur
Try the following:
- open the ePub in
Sigil and
ADE and other ePub readers
- double-check the language metadata in Sigil or your authoring tool
-
check the validity and well-formedness of the ePub