en_tn_lite_do_not_use/exo/01/14.md

made their lives bitter

The difficult lives of the Israelites are spoken of as if they were bitter food that was difficult to eat. (See: rc://en/ta/man/translate/figs-metaphor)

mortar

This was a wet glue or mud put between bricks or stones that held them together when it dried.

All their required work was hard

"The Egyptians made them work very hard" or "The Egyptians forced them to work very hard"