en_tn/luk/11/29.md

This generation

"The people living at this time" (UDB)

It seeks a sign

"They want me to give them a sign" or "Many of you want me to give you a sign." The information about what kind of sign they wanted can be made explicit as in the UDB. (See: rc://en/ta/man/translate/figs-explicit)

no sign will be given to it

"God will not give them a sign" (See: rc://en/ta/man/translate/figs-activepassive)

the sign of Jonah

This could be translated as "what happened to Jonah" or "the miracle that God did for Jonah" (UDB).

For just as Jonah became a sign...so too

This means that Jesus will serve as a sign from God for the the Jews of that day in exactly the same way as Jonah served as a sign from God to the people of Nineveh.

Son of Man

Jesus is referring to himself.