VERB 松开;解开 If you unfasten something that is closed, tied, or held together, or if you unfasten the thing holding it, you loosen or remove the thing holding it. 松开;解开
When Ted was six we decided that he needed to know how to fasten and unfasten his seat belt. [VERB noun]
特德六岁的时候,我们认为他得知道如何系上和解开安全带了。
Reaching down, he unfastened the latch on the gate. [VERB noun]
他伸手打开了门闩。
He once emerged from the toilets with his flies unfastened. [VERB-ed]