however, their disappointment and discontent evidently passes quite quickly when the situation develops into a different one

주어가 2개 인데 왜 3인칭 단수로 취급을 한거죠?
추상명사는 2개가 와도 단수로 취급하나요?

a decision-maker’s knowledge and experience are essential and can contribute to a good decision
이 문장에서는 복수로 취급했는데 말이죠..