en_tn_lite_do_not_use/exo/07/03.md

harden Pharaoh's heart

Here "heart" refers to Pharaoh. His stubborn attitude is spoken of as if his heart was hard. See how you translated this in Exodus 4:21. AT: "will cause Pharaoh to be stubborn" (See: rc://en/ta/man/translate/figs-synecdoche and rc://en/ta/man/translate/figs-metaphor)

many signs ... many wonders

The words "signs" and "wonders" mean basically the same thing. God uses them to emphasize the greatness of what he will do in Egypt. (See: rc://en/ta/man/translate/figs-doublet)

put my hand on ... reach out with my hand on

The words "my hand" represent God's great power. AT: "use my power against ... show my powerful acts against" (See: rc://en/ta/man/translate/figs-metonymy)