decide的形容词形式是decisive；
decisive：adj.决定性的；关键的；坚决的；果断的
相关介绍
The election campaign has now entered its final, decisive phase
选举活动现在已进入了最后的决定性阶段。
The decisive goal arrived against the run of play
这个决定性的得分逆转了场上的局势。
He was a man of decisive action and an adventurous disposition.
他是一个行动果断又爱冒险的人。
