phrase C2 to make something seem uncertain: 对…怀有疑虑，对…表示怀疑 Witnesses have cast doubt on the accused's innocence.证人们对嫌疑人是否清白表示怀疑。 New evidence has emerged which casts doubt on the veracity of his testimony. There are claims that these irregularities are sufficiently serious to cast doubt on the validity of the election results. Subsequent investigations cast doubt on the authenticity of the photographs. However, several intelligence experts have cast doubt on these claims. See also
doubtnoun
cast doubt on someone/something | American Dictionary
cast doubt on someone/something
idiom to cause people to feel uncertainty about something: New evidence has cast doubt on the guilty verdict.