When you submit a task you have two opportunities: 

1. write text
2. submit file or files to a task

You can use the "Comment" button if you would like to ask something from your professor; write your message in the text field and then click on "Send". Or if you would like to submit your task, you can attach it in a file format, and can also write a message, or simply write you answers in the textbox. 

If your task consists of submitting a text, you can click "Task submission", and submit your task in the text field. 

Task results 
When the professor has evaluated your submitted task, you will be able to see your result in the scene's main page in the "Tasks" box's "Result" section.
 

Results of other students

The author of the task has the right to set if students are able to see each other's results.