题目

    When Polly left home that morning, the city was already covered in grey mist. After work, Polly tried 46. _________ (take) her usual bus home 47._________ the fog got too thick, but the bus conductor told her to take the Underground to Green Park and find a taxi there. On the train, as Polly observed the passengers, she had a feeling 48._________ she 49._________ (watch) by a tall man in a dark overcoat. While the rest of the passengers were getting out, she glanced at the faces around her. The tall man was 50._________ to be seen. When Polly got to the station entrance, it was 读“某地等高线地形图”，回答下列各题。 1.图中甲处表示（ ）A. 山顶 B. 山谷 C. 山脊 D. 陡崖2.图中四条登山线路，坡度最陡的是（ ）A. ① B. ② C. ③ D. ④