A：海南岛
B：台湾岛
C：崇明岛
D：舟山群岛
It's very convenient ______ us to buy train tickets now because we can buy them either from the station or on the Internet.
近年来，侵害少年儿童权益的事件频发。细心的小明从四个方面收集了素材，请你阅读并探究相关问题。
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