许下

许下	xǔ xià	to make a promise
许	Xǔ	surname Xu
许	xǔ	to allow / to permit / to promise / to praise / somewhat / perhaps
下	xià	down / downwards / below / lower / later / next (week etc) / second (of two parts) / to decline / to go down / to arrive at (a decision, conclusion etc) / measure word to show the frequency of an action