抽油机井防喷盒处漏油是由于（）不对中引起的密封填料磨损。
A、井口
B、支架
C、光杆
D、游梁
参考答案：C
根据句意，用所给单词的适当形式填空。
1. All flights have ______ (cancel) because of bad weather.
2. Thank you very much for your ______ (introduce).
3. This railway line _______ (connect) London to Edinburgh.
4. He had finally ______ (achieve) success.
5. We are ______ (pride) of what he did.
《素问·上古天真论》“筋骨坚，发长极，身体盛壮”所指女子的年龄段是（）。
A."二七"
B."三七"
C."四七"
D."五七"
E."六七"
