一根光滑的绝缘细杆与水平成倾斜放置，其BC部分在向右的匀强电场中，电场强度E＝2

John likes     1   (read) very much. His father has a library and the boy    2    (read) most of the books in it. So he often    3    (borrow) books from the school library. He reads books when he    4    (be) free and does nothing but reading at home on Weekends. Once he even    5   (read) a novel in class because it was very interesting. Of course he couldn’t hear what the teacher    6   (say). So he    7    (fall) behind. The headmaster had a talk with him and told him    8   (not read) novels in class. At last, he realized that he was wrong and said “I’m sorry, I    9    (not do) it again.” And now he reads books after he finishes    10    (do) all his homework..

脊髓病所致音叉振动觉及位置觉缺失的病变部位在

A．前庭脊髓束

B．红核脊髓束

C．脊髓小脑束

D．脊髓小脑束

E．薄束与楔束

下列名酒，原产地在四川的有（）。

A.茅台酒

B.泸州老窖

C.汾酒

D.全兴大曲

误食大量亚硝酸钠可引起（）。

A.营养不良

B.肠源性青紫症

C.腹泻

D.血细胞增高

E.全身麻痹

空压机气缸内发生敲击声的原因有哪些？