キャッシーは花をつむのをやめた。

topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis

flower; blossom; bloom; petal; cherry blossom; beauty; blooming (esp. of cherry blossoms); ikebana; Japanese playing cards; beauty; (the) best

indicates direct object of action; indicates subject of causative expression; indicates an area traversed; indicates time (period) over which action takes place; indicates point of departure or separation of action; indicates object of desire, like, hate, etc.

to become fine (of fabric); to be checkmated; to be hard pressed; to be at a loss; to reach the limits

indicates possessive; nominalizes verbs and adjectives; substitutes for "ga" in subordinate phrases; (at sentence-end, falling tone) indicates a confident conclusion; (at sentence-end) indicates emotional emphasis; (at sentence-end, rising tone) indicates question

to stop (an activity); to cease; to discontinue; to end; to quit; to cancel; to abandon; to give up; to abolish; to abstain; to refrain