They are returning because of frustrations with U. S. visa policies that make it extremely difficult for skilled workers from high-population countries to obtain permanent-resident visas;

这些人回国的原因是由于遇到了美国签证政策的阻碍，因为美国的签证政策让这些来自人口大国的科技人才要想在美国获得永久性居住签证变得极其困难；

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The us currently limits visas for skilled foreign workers to 65,000 a year, while the number of green CARDS, required for permanent resident status is limited to 140,000 a year.

美国目前将签发给外国熟练工人的签证数量限制在每年6.5万个，而将签发的绿卡(即获得永久居民身份)数量限制在每年14万个。

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The AFL-CIO says all the workers should be able to petition for permanent resident visas that would allow them eventual citizenship, but the chamber says not all of the workers may be eligible for permanent residency.

WSJ: Business, labor still at odds on temporary workers