Nonimmigrants enter the United States for a temporary period of time, and once in the United States, are restricted to the activity or reason for which their nonimmigrant visa was issued.

非移民工人短暂的逗留美国，在美国只能被限制从事他们在签证上说明的原因上的活动。

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The nonimmigrant visa holders may be in the United States as tourists on business or as students.

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