Australia 4-year work visa

457 employer-sponsored work visa (long-stay temporary business visa) is a business work visa valid for 4 years; Visa holders can enter and leave Australia many times during the validity period of the visa, and they can take their families with them. Minor children of the same age can attend public schools for free. Within the validity period of the visa, if the visa holder has worked in Australia for two years, he can apply for a "186 permanent resident visa" (186 permanent residence visa -> PR), that is, an Australian green card.