Complex sentence: Under the Compulsory Military Training Act of 1949 all males, became liable for military service upon reaching 18 years of age, this took affect in 1950, all men aged 18 and over were required to register with the Department of Labour and Employment.
Split into simpler sentences: Under the Compulsory Military Training Act of 1949 all males became liable for military service upon reaching 18 years of age. This took affect in 1950, all men aged 18 and over being required to register with the Department of Labour and Employment.