54. Be careful. The disease called H1N1 flue can _____________(传播) quickly.

53. Playing computer games too much has a bad ___________(影响) on us.

52. Renmin Road is the ___________ (繁忙的) street in our city.

A. 根据句意、汉语提示或首字母写出单词。

51. Mary passed her exam because she studied very ___________(努力).