contract basis

基本解释

General business skills will come in handy, since many graphic designers work on a freelance or contract basis.
一般业务技能会派上用场，因为许多平面设计师的工作一个自由职业者或合同的基础上。
Most of the dodgy food was produced by one American supplier, Menu Foods, which made it on a contract basis for several large companies.
大部分的dodgy食物由一家叫Menu Foods的美国供应商提供，这也使它与很多家公司签订合同。
If there are no full-time positions available , consider asking to work on a contract basis.
如果没有全职的岗位，可以考虑问问做外包的工作。

To ensure that this is done correctly, you might want to hire an SEO specialist on a contract basis.
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Bottom Line: the workforce of today is specialized and highly virtual: working part-time, mobile, from home, and often on a contract basis.
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