Do not expect them to use your voice. Respect the courage each writer has shown in laying the work bare for your inspection, while still unfinished. Try to imagine to understand the person that did want to write the piece the way it's written. With some degree of empathy you may then hope to offer something truly useful to your fellow writer, and gain a useful shift in perspective for yourself as well. Your critique should include information about the following points.
Excessive internalization slows the story.
If the character is thinking or wondering about every action, the writer foreshadows the plot and alienates the readers desire to continue reading. It's not necessary to record each step a character takes. Closing the door, he went to the cupboard, reopened the cabinet to search for a clean glass. Finally after finding one, he carried the carton and clean glass to the table where he pulled out a chair and sat down. It had been a long, hot, tiring day, and, eager to quench his thirst, John poured drank the milk.