叹杏眉
[tàn xìng méi]
'Tanxingmei' directly translates to sigh at/over the apricot eyebrows, 'Apricot eyebrows' are often mentioned in classical Chinese literature/poems to portray delicate feminine features/a young lady. So it could refer metaphorically to someone feeling sorrowful about lost youth/beauty/time or reminiscing over past events associated with love or affection, showing deep emotional involvement.