" Certainly, Narcissa, I shall make the Unbreakable Vow, " he said quietly. " Perhaps your sister will consent to be our Bonder."
“当然,纳西莎,我可以立一个牢不可破的誓言,”他轻声说,“也许你姐姐同意做我们的见证人。”
英语百科
Perpend stone
Perpend stone (parpen, parpend, perpin, and other spellings), bond stone, or tie stone is a structural element building term used by stonemasons and brick masons. Perpend is also a piece in brickwork also called a cross joint or when extending through the entire wall a transverse joint or perpend bond.