I had to work out all my figures two times to make sure that my accounts were accurate.

work 在这里是动词，意思是"工作、计算、运算"。 out 在这里是副词，表示"完全地、彻底地"的意思。 work out 这个短语动词的意思是"计算出、算出"，指通过计算得出结果。