world war two 前面加定冠词吗

前面不加定冠词，例如：

1、In World War two， the Americans fought with the Britain and French against the germans.二战中美国联合英、法两国对德作战。

2、World War Two was worse than World War one.二战比一战更残酷。

3、Torpedo boats played an important role during World War Two.鱼雷艇在第二次世界大战中发挥了重要作用。