Since we are doing an informal proof, I will not name the axioms we are using nor will I attempt to prove the intermediate theorems used to make the proof work.

由于我们在进行不正式的证明，所以我不会为所使用的公理命名，也不会尝试去证明那些用来令证明有效的中间定理。

youdao

Its agents do home visits rather than demanding proof of income, which is handy for those who work in Mexico's vast informal sector.

其代理人做家访，而不是要求收入证明，这对那些在墨西哥庞大的非正规经济部门工作的人来说是个很大的方便。

youdao

The higher fees and burdensome documentation requirements--such as proof of address and Social Security cards--pushed immigrants into informal channels to send money overseas more quickly, less expensively and with fewer questions.

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