Hevowedthathewouldneverdothatagain.他发誓绝不再作那样的事。vow表示发誓。可在vow后加that引导出发誓的内容,也可用vowtodosomething。上句可写成:Hevowednevertodothatagain.Hevowedtodohisbesttowinthegame.他誓言......