Before I recorded some courses in both languages,English and Chinese.A few friends suggested that I recorded some interpretation of the courses without Chinese, only with English. I decided to keep recording courses in both languages, meanwhile I record courses only in English. The content is the same. So I wrote like this " Today I want to try adding a content?" I used "a content" , rather than "some content".
I mean I just add a content. 
For example. before I recorded “Lesson one” with both languages, in English and in Chinese. 
now I decide to record “ Lesson one” with only English. 
“before I recorded” and “ now I decide to record” is the same content. 
My understand is correct?

I rewrite it again, please correct it again. 
Hello, boys and girls. Today I want to try adding a content, A few friends suggested that I recorded some interpretation of the courses without Chinese. Only in English. They want to practice their listening, pronunciation and intonation. Before I only recorded it in both language, English and Chinese. Now I also decided to record the same content only in English. I hope you will like it. First we will learn New Concept English Book 1, Lesson one ---Excuse me. We will divide it into eight parts to learn it. 

another question is 
Some friends suggested that I recorded some interpretation of the courses without Chinese,
in this sentence I used " recorded" . Now I am not sure I should use "record" or "recorded". please help me. Thank you very very much.