Love: ai
Love, I love you, affectionate rather than passionate: ai shiteru
Literally - I’m fond of you, you’re my favorite (person), I love you, in anime, this phrase is usually used when one character makes a proclamation of love to another, especially when it’s the first time he/she has used it: suki desu
Also used to signify “love.” If anything, the phrase “Suki da.” is even more ambiguous than the English “I like you.”: suki - affection, liking