2. Either he or I am to blame. You always put everyone else ahead of you in a sentence, and use the cojugation of the closest subject (I) for the verb when there is an OR in the subject.

3. He wrote a curt (sp?) answer but he soon regretted having sent it. Not sure how you spell curt, kurt, curdt. The subject is the same, so dump the comma.

4. Nothing wrong here if you are referencing TWO separate people. Were this a single person, then you would say,

“The poet/statesman has come.”

And, Sara, above, none (not one) IS a full sentence. One is ALWAYS singluar, my dear. Wake up. Have someone kick you in the back of your chair to awaken you next time you fall asleep in your grammar class.

2.either he or me to blame In correct: you lack a capital sign at the beginning and a period at the end of the sentence. Instead of “either he or me to blame”, put Neither him nor I were to blame.

3.he wrote a curt answer,but he soon regretted having sent. Incorrect: you lack a capital sign. Make sure you specify what he sent.

4.the poet and statesman have come You lack a period and a capital sign.