我们从此便通过电子邮件定期保持着联系。

We have kept in touch regularly since then through e-mails.

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为了避免发动机过早的磨损(非正常)和保持最佳的工作状态，对空气滤清器和压力调节阀pcv进行定期的检查和更换便显得至关重要了。

In order to avoid premature wear engine (abnormal) and maintain the best working condition, the air filter and pressure regulator PCV regular inspection and replacement is crucial.

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自此之后，路边天文便成为定期于尖沙嘴星光大道举行的大型天文推广活动。

Since then, the sidewalk astronomy has been becoming one of the largest scaled astronomy activities held regularly at Avenue of Stars in Tsim Sha Tsui.

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