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- The ball must be stationary. 球必须放定。
- The ball must be visible at all times. 任何时候都必须看得见足球。
- The ball must be free rolling to score a goal otherwise it will be deemed "pushed" by the referee and disallowed. 球必须自由滚入龙门才算进球，否则将被裁判视为”挤入”，从而进球无效。
- After a goal has been scored the ball must be placed on the center spot and the match restarted. 当发生进球后,球必须回到中圈圆点处准备重开进行比赛。
- Sports A resonant metal strip, 24 or 30 inches (61 or 76 centimeters) high, across the bottom of the front wall of a racquets or squash court above which the ball must be hit. 发球限制线：横过网球或橡皮球场地前墙底部的金属条，有24或30英寸(61或76厘米）高，必须把球从上方击过球网
- It must then be hit at the first attempt. The bat must be behind the end of the table. The ball must then hit any part of the table on the server's side,bounce over the net and hit any part of the table on the receiver's side. 之后，球须落在发球一方的台面的任何一点上，弹过横网，并落在接球一方台面的任何一点上。
- The small pit lined with a cup into which a golf ball must be hit. 高尔夫球洞有一个杯子的小洞，高尔夫必须被的打入其中
- As a politician, you must be on the ball in the election. 你是一名政治家,必须在选举中时刻警惕。
- Since he could detect no star's shift, Aristotle concluded that the earth must be stationary. 亚里士多德因为没有测出恒星的位移，于是就断定地球一定是静止不动的。
- If this bird really were a roc, I guessed that the white ball must be its egg. 这只鸟果真是大鹏鸟的话，我猜想这颗白球就一定是它下的蛋了。
- The tackled player carrying the ball must immediately play the ball. 带球的选手必须立刻运起球来。
- And the ball must contain an adequate vent to the pressure port opposite of the downstream sealing port. 球体必须包含一个适当的排气口，对着与下游密封端口相反的压力端口。
- It must be difficult to play various personae in the same movie. 在同一个电影中扮演不同的角色肯定不容易。
- The law provides that these ancient buildings must be preserved. 法律规定，这些古老的建筑应该保存。
- Two flexible antennae mark the extremes between which the ball must pass over the net. 灵活的天线标志着两个极端之间的球必须通过在网络上。
- The ball must then hit any part of the table on the server's side,bounce over the net and hit any part of the table on the receiver's side. 之后球须落在发球一方的台面的任何一点上，弹起越过横网，并落在接球一方台面的任何一点上。
- The work must be finished in one way or another. 这件事必须设法做好。
- In cricket, the ball is delivered overarm. 打板球时，要举臂过肩掷球。
- She must be made to comply with the rules. 必须强迫她遵守这些规则。
- The ball must then hit any part of the table on the server's side, bounce over the net and hit any part of the table on the receiver's side. 之后球须落在发球一方的台面的任何一点上，弹起越过横网，并落在接球一方台面的任何一点上。
