I applied green card with TN. The answer is from my lawyer may help
1）我的理解是如果Perm或140没批，我还可以继续renewTN, 不会被拒。如果140批了，file了485以后，就不能renewTN了。请问我的理解对不对？
your understand is 100% correct. you can renew TN with Perm approved, but not I140. Once you file I140, you have risk to get TN denied because the I140 shows your immigration intention.
2）我听说从140批了到可以file485要四到五年呢，那这期间如果不能renewTN用什么工作呢？不是file485以后才能申请EAD吗，用EAD工作吗？
You understand correct. you cannot summit I485 and EAD unless you are EB1. obvoius you are employ based EB2.
3）我在来现在这个公司前（5年前）为了保持身份，用朋友的公司申请过三个月TN。 他的公司是正规合法的，但没给我发工资。从我护照上看不出问题，但如果申请绿卡，会不会有问题？我怎样才能绕过这段呢？
I bielieve they have record, so you cannot avoid. You have to explain this is leagle. If you were in canada that time, you can say you didn't work for them. If you were in US and more than 3 month, I don't know how you can explain. Maybe just cross your finger.
