You might spend the Fall in London on a law internship, and then the Spring in Brussels working for a Member of the European Parliament.
Some students follow up a spring semester internship with a summer internship in another city.
Most interns are juniors or seniors, but some sophomores may be eligible. In most cases, yes. It is your responsibility to contact your country's consulate or embassy in the United States, and the consulate or embassy of the country in which you wish to intern to determine if you need a visa. This paperwork might be time-consuming, so factor this in, and consider applying at least four to six weeks before the application deadline. Bear in mind that your proficiency will improve.