2 is more correct. 1 is grammatically correct, however, not used in everyday language.

Either can be correct. I wish I were a doctor. I wish I was a doctor. I wish I were fishing. I wish I was fishing.

Pride is to feel a certain loyalty to something or an accomplishment. I am proud of the school I go to. I have Cougar Pride. Ego seems to have a negative aspect to it. He has such a big ego, he will not think of anyone but himself. The word ego is not negative, but in everyday street language, it is usually taken that way.

I am not a doctor, but an ache is more of an ongoing discomfort. Pain seems to be more sharp and direct. A doctor may use both terms depending on the situation. My shoulder aches, but it's not really painful. It's been hurting for a week. But if I broke my shoulder, I would experience pain, rather than aches. Hope this helps!

I believe the simplest way to a happy life is to be completely honest with everyone, have no regrets and recognize that there is a higher power in which we can confide.

Yes, "He can't have been there yesterday" is incorrect. "Have been" points to a time in the past. So the "can" verb needs to agree = "couldn't have". Could vs. could have = The word "could" indicates an ability. Adding "have" to it indicates an ability in the past. I could go to the store. = I have the ability to go to the store. I can go to the store. He could be sick = It is possible he is sick. Or he has the ability to be sick. I could have gone to the store. = (notice "go" has to change to "gone" because the sentence becomes past tense with "have".) I had the ability to go to the store. This sentence also indicates that I did not go to the store, even though I had the ability. I couldn't go to the store = I wasn't able to go to the store. I couldn't have gone to the store = I wasn't able to go to the store. Even if I wanted to, I didn't go to the store. Hope this helps!

"Accomplish" points to the end of a large job. Climbing a mountain would be an accomplishment. "I'm so happy for you! That is such an accomplishment!" Most of the time it is used as a noun. "Complete" is simply bringing something to end. "I completed my homework." "Finish" is the same as "complete". But the word "complete" is more formal. "I finished my homework." "Sarah finished her college degree. That is a major accomplishment for her."

To "argue their case", a person would tell the another person their view on a situation. The phrase comes from a court of law when a lawyer would state all the facts and show all the evidence supporting their case, or story, to the judge. In everyday usage, a child who tracks mud into the house would argue his case to his mother saying that it was raining and he could not avoid getting muddy. Or your product is better than the other store's product and you argue that case to the customer. Or if an employee is late for work, he may argue his case to his boss. Hope this helps. Good luck! =)