甜

甜 (tián) is the adjective for the taste 'sweet' — sugar, honey, ripe fruit, candy, dessert. Beyond food, Chinese uses 甜 figuratively for pleasant sounds and faces: 嗓音很甜 ('a sweet voice') and 笑得很甜 ('to smile sweetly') are completely natural and not the cliche they would be in English. 甜 also extends to romantic relationships and life satisfaction — 日子过得很甜 ('life is sweet') or describing a couple as 很甜 ('lovey-dovey, cute together').

Note that 'sweet' meaning 'kind' in English (a sweet person = nice) does NOT map to 甜; use 善良 or 贴心 for that. The opposite tastes are 苦 (bitter), 酸 (sour), 辣 (spicy), 咸 (salty).