Complex sentence: The protests coincided with the events of Prague spring in neighboring Czechoslovakia--raising new hopes of democratic reforms among the intelligentsia--and culminated in the Warsaw Pact invasion of Czechoslovakia on 20th August, 1968.
Split into simpler sentences: The protests coincided with the events of Prague spring in neighboring Czechoslovakia--raising new hopes of democratic reforms among the intelligentsia. The political crisis culminated in the Warsaw Pact invasion of Czechoslovakia on 20th August, 1968.