To harbor evil intentions; to have ulterior motives; to be ill-intentioned and unpredictable.
那个新来的经理表面和善，但有人觉得他心怀叵测，目的不纯。
The new manager seems kind on the surface, but some people feel he harbors ulterior motives and impure intentions.
Era:
Ancient
Frequency:
Story:
During the Three Kingdoms period, Cao Cao was preparing to lead his army south to attack Sun Quan and Liu Bei. Fearing that Ma Teng, the Governor of Liangzhou, might seize the opportunity to cause trouble, he adopted the advice of his strategist Xun You.
Cao Cao deceitfully appointed Ma Teng as the General Who Conquers the South and tricked him into coming to Xuchang, intending to assassinate him there.
Ma Teng did not believe his nephew Ma Dai, who warned him that Cao Cao was a man harboring evil intentions (心怀叵测). Thus, Ma Teng went to Xuchang with his son Ma Xiu, where he was subsequently killed by Cao Cao.
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