that / it is essential / come to / our factory / one of the engi

that / it is essential / come to / our factory / one of the engineers / two weeks / for a period of
【正确答案】：It is essential that one of the engineers come to our factory for a period of two weeks.
【题目解析】：本句句意为其中一个工程师来我们工厂两个工厂是很有必要的。根据给的提示词，我们能知道it is essential that肯定要放句首，因为it是形式主语，that后面要跟真正的主语，即主语从句。剩下的再根据主谓宾，所以答案如上。