There are fourteen errors in the use of punctuation marks in the following text. Rewrite the text correcting the errors.

Student  :Excuse me sir I want to discuss with you some grammatical problems.
Teacher :What class are you in
Student :Sir I am in class XI I am a newly admitted student herE-
Teacher :Okay tell me your problems
Student : I want to understand the difference between a phrase and a clausE-
Teacher :Dont worry. Ill help you understand the differencE-