be, smell, taste
The air smelled sweet and clean.

make sth
find sth
I found the dessert a little sweet for my taste.

extremely, fairly, very, etc.
a little, slightly, etc.
enough
Is the tea sweet enough for you?

sickly
an overpowering, sickly sweet smell

be, look, seem, sound
keep sb (informal)
He'd promised her a new car, just to keep her sweet (= keep her in a good mood).

awfully, really, terribly, very
sickeningly, sugary
a sickeningly sweet smile

to
She was really sweet to me.

dear sweet …
My dear sweet sister Jillie.

short and sweet
I'll keep it short and sweet (= speak briefly).

sweet and innocent
She looked so sweet and innocent.

sweet little
a sweet little smile

Sweet is used with these nouns:
air, apple, aroma, champagne, cherry, cider, coffee, corn, craving, cream, deal, dessert, dish, disposition, drink, embrace, face, flavour, flesh, food, fragrance, fruit, gesture, girl, grape, guy, innocence, jar, kiss, lady, melody, memory, music, odour, onion, orange, pastry, pepper, perfume, potato, relief, revenge, roll, sauce, scent, sherry, smell, smile, snack, sound, spot, talk, taste, tea, thing, tone, treat, trolley, voice, wine, wrapper