Formal:
* मैं तुमसे प्यार करता हूँ (Main tumse pyaar karta hoon) - (Male speaker)
* मैं तुमसे प्यार करती हूँ (Main tumse pyaar karti hoon) - (Female speaker)
Informal:
* मुझे तुमसे प्यार है (Mujhe tumse pyaar hai) - This is the most common and straightforward way to say "I love you."
* तुमसे प्यार करता हूँ (Tumse pyaar karta hoon) - (Male speaker)
* तुमसे प्यार करती हूँ (Tumse pyaar karti hoon) - (Female speaker)
More affectionate:
* मैं तुमसे बहुत प्यार करता हूँ (Main tumse bahut pyaar karta hoon) - (Male speaker)
* मैं तुमसे बहुत प्यार करती हूँ (Main tumse bahut pyaar karti hoon) - (Female speaker) - This means "I love you very much."
* तुम्हें बहुत प्यार करता हूँ (Tumhen bahut pyaar karta hoon) - (Male speaker)
* तुम्हें बहुत प्यार करती हूँ (Tumhen bahut pyaar karti hoon) - (Female speaker) - This also means "I love you very much."
Romantic:
* मैं तुमसे मोहब्बत करता हूँ (Main tumse mohabbat karta hoon) - (Male speaker)
* मैं तुमसे मोहब्बत करती हूँ (Main tumse mohabbat karti hoon) - (Female speaker) - This conveys a more intense, passionate love.
Important Note: The pronoun "tum" (you) is used when addressing someone familiar, while "aap" (you) is used in a more formal context. If you're unsure which one to use, it's best to err on the side of formality and use "aap".