题目

阅读下面短文，从短文后各题所给四个选项（A、B、C和D）中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑 Christmas 1940 makes me misty-eyed every time I think about it. In the hard times, people 1 one another. We 2 food, clothing, bedding and household items and gave them to the needy. That Christmas we students found ourselves 3 toys we collected and lading packages for 4. As we presented the gifts, we saw 5 in many faces, especially those of the children. We had a few more 6 to make on Christmas morning. The air was heavy and frozen to 烯烃A在一定条件下可以按下图所示进行反应： （D是，互为同分异构体，互为同分异构体。） 请回答下列问题： （1）A的结构简式是     ▲     ；G1的结构简式是     ▲     。高*考*资*源*网 （2）用系统命名法命名有机物B，B的名称是     ▲     。 （3）框图中属于取代反应的是     ▲     。（填数字代号） （4）E→F2的化学反应方程式        ▲        ，属于    ▲    反应。