Considering the sentences below when teaching/learning the productive skills:

I. One of the characteristic of a genuine communication is the information gap which exists between speaker/writer and listener/reader.

II. One of the characteristics of a communicative activity is the focus on content of the topic and not on the form.

III. One of the characteristics of a non-communicative activity is the focus on the linguistic form and not on the content.

IV. Another characteristic of a communicative activity is the desire to communicate by the people involved.

Is (are) correct