prove/proof/improve/approve/approval/progress/certificate/license/diploma
记忆：
1. prove [ pru:v ] vt. 证明, 证实 What he predicted proved true. 他的预言证明是真的。
2. proof [ pru:f ] n. 证据, 试验 Can you present any proof to support your idea?你能拿出证据证明你的观点吗？
3. improve [ im5pru:v ] v. 改善, 改进 With the living conditions improved, people have a longer life expectation.随着生活条件的改善，人们有望更长寿。
4. approve [E5pru:v] vi. 赞成, 满意 vt. 批准, 通过 I knew my parents wouldn't approve of what I had done. 我知道我的父母不赞成我所做的事情。
5. approval [E5pru:v(E)l] n. 赞成, 承认, 正式批准 He showed his approval by smiling. 他用微笑表示赞成。
6. progress [ 5prEu^res ] n. 前进, 进步, 发展 No progress is also a guilt. 没有进步也是一种罪过。
7. certificate [ sE5tifikit ] cert-i-fic-ate 确证做过的事， n. 证书, 证明书 A document testifying to the truth of something The marriage certificate shows that he has been married.结婚证表明他已经结过婚了。
8. diploma [dI5plEJmE] n. 文凭, 毕业证书 A document issued by an educational institution, such as a university, testifying that the recipient has earned a degree or has successfully completed a particular course of study. Our secretary had diplomas in both pedagogy and linguistics. 我们的书记既有教育学文凭，也有语言学文凭。
9. license [5laIsEns] n. 许可(证), 执照 vt. 许可, 特许 Proof of permission granted, usually in the form of a document, card, plate, or tag When did you receive your driving license?你何时获得驾驶执照的？
另类阅读：
These proofs can prove that we have made progress in our efforts in improving our study. I think we will soon get the certificates for it.