注:Dreams (梦想, dreams in one's sleep) are something that cannot be realized. On the other hand, ideal (理想, dreams of one's future) is something that is hopeful and possibly realizable. People usually say “共产主义的理想一定会实现” but do not say “共产主义的梦想一定会实现” mainly because 理想 is realizable but 梦想 is un-realizable.