Around xx tonnes of ghost net was collected for a half-day clearance exercise.

是次半日的清理行动中约清除了两吨鬼网。

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Health officials recommend that all seniors get clearance from their physicians-particularly if they have a history of heart problems-before they start an exercise program.

健康官员建议每个老年人、特别是有心脏病史的人，在从事运动之前应该由医生开个清单。

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The committee said it saw no reason why the controlled archive should grow, given that the legacy clearance exercise had now been completed.

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And of course, make sure to get medical clearance from your doctor before stepping up (no pun intended) your cardiovascular exercise regimen.

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