zero-sum game英 [ˈziərəuˈsʌm ɡeim] 美 [ˈzɪroˈsʌm ɡem],零和竞赛,零和; 零和比赛; 零和博奕sony as a security tag with a true zero - ball version of paul to zero ball game.用索尼作为保的真实版保零球游戏.
porch英[pɔ:tʃ]美[pɔ:rtʃ]n.门; ,走廊网络门口; 门廊,游廊; 门廊复数:porches1** there a light in the porch or garden?门廊或花园里吗?2jack scratched at the porch door, wanting in.杰克在抓游廊的要进来。