Formal:
* நான் உன்னை நேசிக்கிறேன் (naan unnai naesikkiraen) - This is the most formal way to say "I love you." It is used in writing and in situations where you want to express a deep and sincere love.
Informal:
* உன்னை ரொம்பப் பிடிக்கும் (unnai rombap pidikkum) - This translates literally to "I like you very much." It is a more casual and affectionate way to express love.
* நீ எனக்கு ரொம்பப் பிடிச்சு (nee enakku rombap pidichchu) - This means "I like you very much." It is a slightly more affectionate way to say "I love you" and is commonly used among friends and family.
Romantic:
* நான் உன்னைப் பாத்து காதலிச்சு போயிட்டேன் (naan unnai pattu kaadhalichchu poyitten) - This means "I fell in love with you." It is a romantic and passionate way to express love.
It's important to note that the context and the relationship between the speakers will influence the best way to say "I love you" in Tamil.