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Many obscure grapes exist in california because immigrants brought them over and planted them in their backyards .

“许多不知名的葡萄品种之所以会出现在加利福尼亚，是因为早期的移民千里迢迢地把它们从故乡带来，种植在自己的后院之中。

Town halls are obliged to register even illegal immigrants .

市政厅有义务登记即使不合法的移民。

Yet both are illegal immigrants .

然而她们两人都是非法移民。

An ageing continent needs immigrants .

一个不断老龄化的大陆需要移民。

Tighten the points-based system for selecting immigrants .

趋紧对于优秀移民的筛选系统。