这个和unbelievable意思相近
示例
A：He betrayed his county.
B：I can't believe it.
A：他背叛了他的国家。
B：简直无法相信！
A：I can't believe it.
B：Well, nothing is impossible.
A：我简直不敢相信。
B：嗯，一切皆有可能。