jeśli to ma być jakiś formalny grzeczny english to może skonsultuj to jeszcze z kimś innym a jak taki żeby się dogadac to ja bym napisała tak:
1. obviously , as I wrote earlier
2. maybe you didn't receive my e-mail albo It seems to me that you didn't receive my e-mail
3. beacuse of albo due to specific conditions in our school
3. by virtue of albo też due to specificity of our market