Formal:
* 很高兴认识您 (hěn gāoxìng rènshi nín): This is the most formal and polite way to say it. Literally translates to "very happy to meet you."
* 幸会 (xìnghuì): This is a more traditional and formal expression, often used in business settings or with older people. It means "it's a pleasure to meet you."
Informal:
* 很高兴认识你 (hěn gāoxìng rènshi nǐ): This is a more casual way to say it, used with friends or people you know well. Literally translates to "very happy to meet you."
* 认识你很高兴 (rènshi nǐ hěn gāoxìng): This is another informal way to say it, meaning "I'm very happy to meet you."
Adding a little extra:
* 很高兴认识您，希望以后能常联系 (hěn gāoxìng rènshi nín, xīwàng yǐhòu néng cháng liánxì): "I'm pleased to meet you, I hope we can keep in touch."
* 很高兴认识您，谢谢您今天抽出时间来 (hěn gāoxìng rènshi nín, xièxie nín jīntiān chōu chū shíjiān lái): "I'm pleased to meet you, thank you for taking the time to meet with me today."
It's best to choose the appropriate expression based on the situation and your relationship with the person you are speaking to.