What mammals give birth to young?

All modern mammals are viviparous animals. The exception to the rule are two animals, the platypus and the echidna, which lay eggs. Despite this, not all of them are capable of producing fully formed cubs. For example, in marsupials, offspring are immature, and from the main life support functions they can only breathe on their own. And they continue to form in the mother’s pouch. And in some herbivores, a young individual can run and hide without the help of the mother almost immediately after birth.