R.Please correct these sentences
1.I live on Dubai-Sharjah border / I live on the border of Dubai and Sharjah
OR the border between Dubai and Sharjah
2.I did the cleaning by myself. OK
3.On behalf of Eid, there will be no classes on 15th and 16th of next month.
No. If you're making an announcement on behalf of Eid, you might say
"Eid advises that there will be no classes on 15th and 16th of next month." OR "On behalf of Eid, I advise that there will be no classes ..."
4.Office hours are not a problem for me.
Student or Learner