完形填空

      Hey, I'm Simon. I have a strong and faithful dog, Bruce. The dog likes1with me. Sometimes he also follows my father to work. One morning when my father worked in the field, he2 his coat and put it under a big tree. He turned  to the dog and said,“3my coat, Bruce!” Bruce sat down on the coat. Later, my father remembered he had to buy some food.  4 he hurried to the shop.   5 shopping, he went home directly and forgot completely about his 6 and the dog. In the evening, I looked for my dog7 in the house, but I8 find him. At this time, my father suddenly remembered his coat and the dog. He went back to the tree   9. He found that Bruce was 10 sitting on the coat!

       沧州刘士玉孝廉，有书室为狐所据。白昼与人对语，掷瓦石击人，但不睹其形耳。知州①平原董思任，良吏也，闻其事，辄自往驱之。方入书室，忽檐际朗言曰：“公为官颇爱民，亦不取钱，故我不敢击公。然公爱民乃图好名不取钱乃畏后患耳故我亦不避公。公休矣，毋多言取困②。”董狼狈而归，咄咄不怡者数日。刘一仆妇甚粗蠢，独不畏狐。狐亦不击之。或对语问其故，狐曰：“彼虽下役，乃真孝妇也。鬼神见之犹敛避，况我曹乎？”刘乃令仆妇居此室。狐是日即去。

                                                                                                                                                                              （选自《阅微草堂笔记》，有删改

【注释】①知州：官职名称。②取困：自取尴尬。

如图所示，△ABC中，AB=AC，过AC上一点作DE⊥AC，EF⊥BC，若∠BDE=140°，则∠DEF=（　　）