Explain in your words what was the main principles of Apartheid Law.

The main principles of Apartheid Law are the prohibition of mixed marriages between whites and people of color.

The Distinction of individuals based on their race; establishment of a register in which all races are listed.

 the obligation for over 16 years Blacks  to get a pass government  allowing them to circulate in the white neighborhoods.

 separation in all public places: toilets, benches, fountains .. With aim to eliminate contact between whites and blacks.