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He started his ace left halfback on the second half .

在下半场,他派了出色的左中卫上场.

E.g. he was a halfback before he becomes a quarterback .

他在成为四分卫之前是名前卫。

With 30 seconds to go in the football game , the harvard halfback scored a touchdown to beat yale .

在离橄榄球比赛结束前还剩30秒钟时，哈佛队的中卫获得底线得分，结果击败了耶鲁队。

The halfback pretended to run forward , then cut back to his left and took the ball the other way .

那中卫假装向前跑，接着突然变向朝左跑，把球带向另一边。

The injured right halfback was compelled to sit out the rest of the play .

受伤的右中卫只好退出比赛，在剩下的时间里坐在一旁。