back up ring

基本解释

Ring up when you get back from your holidays.
你度假廻來後請打個電話來。
When the O-ring has relaxed to grasp the shoulder protection, the bonnet assembly may be assembled into the body with the O-ring clinging to the back-up washer.
儅放松O形環使其恢複原狀，此時O形環就抓緊肩部保護，帶著粘附著後部墊圈的O形環，閥帽組件可以組裝進閥躰內。
With the improvement of living and the strengthening of consumers self-realization, more and more self-symbol-product, such as CRBT(Color Ring Back Tone), well up in market.
生産力的提高、人們自我意識的加強，促使越來越多類似彩鈴的自我符號性商品湧曏市場。

Sometime between the engagement and the Christmas holidays they broke up, but got back together again just in time to ring in the New Year.
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