三、单句改错(共10小题;共10分)

　　41. Most of students in my class come from the countryside.

　　42. Lily is more careful of the twins.

　　43. After graduation, she turned a nurse.

　　44. There was heavy rain last night.

　　45. Yesterday for him was happiest day.

　　46. Tom is the shortest of his three brothers.

　　47. Greg is taller of the two.

　　48. One of the three foreign visitors is a Japanese, other two are

　　Australians.

　　49. The Yellow River is second longest river in China.

　　50. Today was my the first day of school in China.