n.擊穿;飛?。粐?yán)重打火
動(dòng)詞arc的現(xiàn)在分詞.
The sun appears to move in an arc across the sky. 太陽看起來在天空以弧線運(yùn)行。
An early instrument for measuring altitude of celestial bodies, consisting of a90= graduated arc with a movable radius for measuring angles. 象限儀用來測(cè)量天體緯度的一種早期工具,由一個(gè)有90度刻度的圓弧和一個(gè)用來測(cè)量角度的可移動(dòng)的半徑構(gòu)成