She distrusted his motives for wanting to see her again.
她怀疑他想再见她一面是别有用心。
He acted from base motives.
他的行为动机卑鄙。
He tried to get a fix on the young man's motives, but he just couldn't understand him.
他努力了解这个年轻人的动机，但就是弄不清楚。
Their motives remain a mystery.
他们的`动机仍然是个谜。
Her motives for helping are questionable.
她帮忙的动机令人生疑。