这些科学家已去过美国两次了的翻译：The scientists has gone to the United States twice 什么意思？中文翻译英文，英文翻译中文，怎么说？

青云英语翻译

These scientists have twice visited the United States

The scientists has gone to the United States twice

These scientists have gone to the American two times

These scientists have already went to the United States has twice

The scientists has gone to the United States twice