从2000 年至 2008 年,我曾经在 xxx 公司当 MIS executive.Translate to Engl

2) 2000年 2008年 本人就职于XX公司,任信息管理主管一职.
If you are working on your resume,you are probably referring to a period of work experience.I don't think the first one is grammatically incorrect,but the latter looks natural.
Here's a sample of work experience on a job application.I hope you'll find it helpful.
Key Holder,Montblanc
April 2001 - February 2005
• Opened new specialty boutique
• Placed orders to restock merchandise and handled receiving of products
• Managed payroll,scheduling,reports,email,inventory,and maintained clientele book and records
• Integrated new register functions
• Extensive work with visual standards and merchandising high-ticket items
Sales Associate,Nordstrom - Collectors and Couture Departments
July 1999 - April 2001
• Merchandised designer women's wear
• Set-up trunk shows and attended clinics for new incoming fashion lines
• Worked with tailors and seamstresses for fittings
• Scheduled private shopping appointments with high-end customers

过去完成时与一般过去时的区别
时间状语不同：过去完成时在时间上强调“过去的过去”；而一般过去时只强调过去某一特定的时间。
比较：They had arrived at the station by ten yesterday.
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