Complex sentence: He called on the party to further entrench party orthodoxy among young people, effectively re-introducing restrictions on freedom of speech, the press, and assembly that was prominent during the lax political environment of the late 1980s.
Split into simpler sentences: He called on the party to further entrench party orthodoxy among young people, effectively re-introducing restrictions on freedom of speech, the press, and assembly. These freedoms were prominent during the lax political environment of the late 1980s.