The police said they-----(remind)

The police said they_____(remind)young parents not to let their children go out alone in the news,为什么填reminded,不填would remind呢?谷先生已经决定和家人去美国度假。Mr Gu _has__ __made_ _a__ _decision__to go to the USA_?__ a holiday with his family。为什么用for has made up his mind /for，请帮我分析一下这个短语及意思