同学你好，该知识点来自沪江网校《大学英语四六级【连读班】》的课程，想要更系统的学习，欢迎进入课程学习。不仅可以和更多的同学一起学习，而且还有老师、助教随时的学习指导和知识点解答哦。

同学好，
combine和combination在作名词时还说有区分的哦。
可以从英语释义去了解细节区分。

com·bine  /ˈkɒmbaɪn/
1.
( BrE also also ˌcombine ˈharvester ) a large farm machine which cuts a crop and separates the grains from the rest of the plant 联合收割机
2.
a group of people or organizations acting together in business 集团；联合企业

combination
1.[ C ] two or more things joined or mixed together to form a single unit 结合体；联合体；混合体
eg. His treatment was a combination of surgery, radiation and drugs. 对他的治疗是把手术、放射和药物治疗结合为一体。
2.[ U ] the act of joining or mixing together two or more things to form a single unit 结合；联合；混合
eg. The firm is working on a new product in combination with several overseas partners. 这家公司与几家海外合伙人在联合开发新产品。
3.[ C ] a series of numbers or letters used to open a combination lock （用于开密码锁的）数码组合，字码组合
eg.I can't remember the combination. 我不记得密码锁的数码组合了。
4.combinations ( BrE ) [ pl. ] a piece of underwear covering the body and legs, worn in the past （旧时的）连裤内衣

祝进步。