恐縮， きょうしゅく
1. feeling (much) obliged, being (very) grateful, being thankful
2. feeling sorry (for troubling someone), feeling ashamed (e.g. of an error), feeling embarrassed (e.g. by someone's compliments, hospitality, etc.)
3. shrinking back in fear
感激不尽，深表谢意，心怀感激；感到抱歉(因给他人添麻烦)，感到羞愧(例如因犯错)，感到尴尬(例如因他人的赞美、款待等)；畏缩不前