It is important and necessary ______ us all to learn English well.
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男性,50岁,干咳,喘鸣,胸闷3个月。既往体健。胸片示右肺肺门增宽可见一边缘毛刺3cm×2cm块状影
On Sunday they could not open ______ of the front windows.
A. both
B. some
C. any
工艺装置内露天布置的塔、容器等,当顶板厚度等于或大于()mm时,可不设避雷针保护,但应设防雷接地。
A. 1
B. 2
C. 3
D. 4