群龙无首 A flock of dragons without a head. The Handian dictionary defines it as a group with no one to lead it, so that it cannot act together. Its example comes from Yao Xueyin’s novel Li Zicheng: “But a flock of dragons without a head will never become a great force.”
火车跑得快，全靠车头带 A train runs fast because the engine pulls it. In October 2016, a People’s Daily report on grassroots Party organizations used this line.
The first phrase comes from the Book of Changes, where it is a good omen: “A flock of dragons appears without a head. Good fortune.” Taiwan’s national dictionary explains the old sense. When many worthy people rise together, none should push forward to lead.