中英成语俚语800对135：肺腑之言
肺腑之言 Speak one's conscience.
eg：I am speaking my conscience to you in giving you my suggestion.
中英俚语俗语来源：史记：“田蚡以肺腑为京师相。”
同义词：披肝沥胆、由衷之言 Lay bare one's heart