1. Not once did it occur to Michael that he could one day become a top student in his class. 迈克尔一次也没有想过有一天他会成为班里的尖子生。
2. The mamba will strike not once, but repeatedly, injecting large amounts of potent neuro- and cardiotoxin with each strike. 黑曼巴不会立即发起攻击,但是会不断地,释放大量的强力神经和心脏毒素。