I have played around with plain tex for a while now and can't figure out how to get back to justified text after e.g. \raggedright. Can it really be that I have to use \raggedright in a group \begingroup\raggedright...\endgroup in order to restore justified text? There has to be a way to get back the original justifying.
edit: I could get something similar to justified texts by using
\spaceskip3pt plus 2pt minus 1pt
But this is not the original justifying.

\show\raggedrightto have TeX stop and show what it is defined as. – ShreevatsaR Jul 08 '18 at 07:25plain.texfor its definition before. – nox Jul 08 '18 at 07:33