Formal:
* ཁྱེད་ལ་སླེབས་པར་དགའ་བ་འདུག (khye la leb par ga wa dug): This translates literally to "I am happy you arrived" and is a more formal way to express welcome.
* ཁྱེད་རང་ལ་སླེབས་པར་དགའ་བ་འདུག (khye rang la leb par ga wa dug): Similar to the previous one, but with a slightly more respectful "khye rang" (you) instead of "khye" (you).
Informal:
* ཁྱིམ་ལ་ཕྱིར་ལོག་པར་དགའ་བ་འདུག (khim la phir log par ga wa dug): This translates literally to "I am happy you returned home."
* ཁྱིམ་ལ་ཕྱིར་ལོག་པར་དགའ་ཚོར་འདུག (khim la phir log par ga tsor dug): Similar to the previous one, but emphasizing the feeling of happiness.
You can also use a more specific phrase depending on the situation:
* ཁྱིམ་ལ་ཕྱིར་ལོག་པར་དགའ་བ་ཆེན་པོ་འདུག (khim la phir log par ga wa chen po dug): This translates to "I am very happy you returned home" and expresses greater enthusiasm.
* ཁྱེད་རང་ལ་ཕྱིར་ལོག་པར་རེ་སྒུག་བཞིན་ཡོད (khye rang la phir log par re gug zhin yod): This translates to "We were waiting for your return" and is a warm way to welcome someone back.
Remember that the best translation will depend on the specific context and your relationship with the person you are welcoming.