妈妈要去工作了可以用英文表达为: "Mom is going to work."

这句话的来源是英语中"mom"这个词指的是"妈妈"，"to go"这个短语表示"去"，"work"这个名词指的是"工作"。

一些英文例句并附有中文翻译：

"Mom has to leave for work early tomorrow morning." (妈妈明天早上得早点去上班。)
"My mom works as a nurse at the hospital." (我妈妈在医院当护士。)
"Mom, can you pick me up from school after you finish work?" (妈妈，你下班后能来接我吗？)