Formal:
* 妈妈，您好！ (Māmā, nín hǎo!) - This is the most formal way, literally meaning "Mom, hello!"
* 妈妈，您早！ (Māmā, nín zǎo!) - This means "Mom, good morning!" and is appropriate for the morning.
* 妈妈，您下午好！ (Māmā, nín xiàwǔ hǎo!) - This means "Mom, good afternoon!" and is appropriate for the afternoon.
* 妈妈，您晚上好！ (Māmā, nín wǎnshàng hǎo!) - This means "Mom, good evening!" and is appropriate for the evening.
Informal:
* 妈妈，你好！ (Māmā, nǐ hǎo!) - This is a more casual way of saying "Mom, hello!"
* 妈，你好！ (Mā, nǐ hǎo!) - This is even more informal, using the shortened version of "妈妈" (Māmā) and is more appropriate for close family members.
* 妈，你早！ (Mā, nǐ zǎo!) - This means "Mom, good morning!" and is informal.
* 妈，你下午好！ (Mā, nǐ xiàwǔ hǎo!) - This means "Mom, good afternoon!" and is informal.
* 妈，你晚上好！ (Mā, nǐ wǎnshàng hǎo!) - This means "Mom, good evening!" and is informal.
Other options:
* 妈，回来了！ (Mā, huílai le!) - This means "Mom, I'm back!" and is a common greeting when you return home.
It's important to consider the relationship with your mom and the context when choosing the appropriate greeting.