He is the secret head of a large illegal gambling ring which use the computer for its operations.

他是一个秘密的，大的，非法的赌博团伙的头,那个团伙用这个电脑来操作。

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And Transport for London are always telling people to not to use the minicab, illegal minicab drivers,

伦敦交通局经常警告市民，不要坐不合法的微型出租车，

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Some companies use it even though it is illegal.

尽管非法，有的公司也用。

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