Although trains may use energy more (i)___ than do automobiles, the latter move only when they contain at least one occupant, whereas railway carriages spend a considerable amount of time running up and down tracks (ii)___ , or nearly so.

　　Blank (i)

　　Blank (ii)

　　A. lavishly

　　D. vacant

　　B. efficiently

　　E. unimpeded

　　C. routinely

　　F. overloaded

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