Complex sentence: In 1921, ship owners attempted to take advantage of these conditions by reducing wages, in response to which, the chief trade union representing American marine engineers, the Marine Engineers Beneficial Association (MEBA), went on strike.
Split into simpler sentences: In 1921, ship owners attempted to take advantage of these conditions by reducing wages. In response, the chief trade union representing American marine engineers, the Marine Engineers Beneficial Association (MEBA), went on strike.