已知底面ABCD是平行四边形,点E、H分别是BC和AD的中点
那么：EC//HD且EC=HD
所以：四边形ECDH是平行四边形
则可知点O是对角线HC的中点
又点G是PC的中点
那么GO是△PHC的中位线
即有：GO//PH
因为PH不在平面GED内,GO在平面GED内
所以：PH//平面GED
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Dear friends, I will tell you about my last weekend.
亲爱的朋友们，我将告诉你关于我的周末。
On last Saturday, my parents and I went to the Beishan park to play. First, we watched the flowers. Then, we climbed the mountains. Finally, we have flew the kite.
We have played a morning. In the afternoon, we went to my grandparents' family to visit my grandparents. Except me, other family members talked a lot. I played outside.In the evening,my parents and I took a train to go to Yanji to take part in a English Contest.
在上周六，我和我的父母去了北山公园玩。首先，我们看到鲜花。然后，我们爬了山。最后，我们飞的风筝。我们玩了一个上午。在下午，我们去爷爷奶奶家看望我的祖父母。除了我以外，其他的家庭成员谈了很多。我在外面玩。在晚上，我和父母乘火车去延吉参加英语竞赛。
And on last Sunday,I went Yanji.I went to Yanji hotel to join the conpetation.I fell very happy.And at noon,we had lunch at KFC.The foods is tasty.I ate a lot.
And in the afternoon,we went to the zoo to took some pictures.We played happily.And at three o'clock,we went home.I fell happy and tired.
在上周日，我去延吉。我去了延吉的酒店加入合作化。我感到很高兴。中午，我们在肯德基吃午饭。食物很好吃。我吃了很多。在下午，我们去动物园拍了一些照片。我们玩得很开心。在三点的时候，我们就回家了。我感到高兴和厌倦。
What do you think of my last weekend?
你认可我的周末吗?
