There was a strict rule against turning round until one gave the signal, when all turned at once.
有一条严格的规定，在一个人发出信号，所有人一起转身之前，所有的人都不得转身。
2
All flowing water, though it appears to be uniform, is actually divided into extensive inner surfaces, or layers, moving againstone another.
所有流水尽管看起来是一样的，实际上是分成了大量相互碰撞的内在表层。
《柯林斯英汉双解大词典》
3
All this presupposes one essential detail, says Atholl Anderson, professor of prehistory at the Australian National University: the Lapita had mastered the advanced art of sailing against the wind.