1·The motive for the killing is unknown.
杀人的动机不明。
—— 《柯林斯英汉双解大词典》
2·There seemed to be no motive for the murder.
这起谋杀案看不出有什么动机。
—— 《牛津词典》
3·Police have ruled out robbery as a motive for the killing.
警方已排除了抢劫是杀人的动机。
—— 《柯林斯英汉双解大词典》
4·The police have excluded theft as a motive for the murder.
警方已排除这起谋杀案中的偷窃动机。
—— 《牛津词典》
5·Their motive is money, and they will stop at nothing to get it.
他们的动机是钱,因此他们将不顾一切地捞钱。
—— 《柯林斯英汉双解大词典》