Complex sentence: Soon after beginning work at Lenin Shipyard (now Gdańsk Shipyard), he became a trade union activist, for which he was persecuted by the Communist authorities, placed under surveillance, fired in 1976, and arrested several times.
Split into simpler sentences: Soon after beginning work at the Lenin Shipyard (now Gdańsk Shipyard), he became a trade union activist. For this he was persecuted by the Communist authorities, placed under surveillance, fired in 1976, and arrested several times.