你好：区别如下：
poignant
伤心至极的; 辛酸的, 痛切的
令人心碎的, 深深打动人的; 强烈的, 深刻的
It is especially poignant that he died on the day before his wedding.
他在婚礼前一天去世了, 这尤其令人伤感.
pathetic
adjective
arousing pity, especially through vulnerability or sadness
引起怜悯的,可怜的；可悲的
she looked so pathetic that I bent down to comfort her.
她看上去那么可怜,于是我弯下身去安慰她.
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