Fastening and unfastening上;卸扣
unfastening device解脫裝置
1.He unfastened the buckles and took off the coat.
漢他解開扣子,把上衣脫掉。
2.You may unfasten your seat belt now.
漢現(xiàn)在可以松開您的安全帶了。
1. loosening the ties that fasten something;
"the tying of bow ties is an art; the untying is easy"