anchor.diff:    <tr>
       <th class="head">Username</th>
       <th class="head">Full Name</th>
  -    <th class="head">Team-member role (duty)</th>
  +    <!--<th class="head">Team-member role (duty)</th>-->
       <th class="head">Email Address</th>
       <% if @teammate_review_allowed %>
         <th class="head">Action</th>
  
positive.code:     <tr>
        <td><%= member.user.name %></td>
        <td><%= member.user.fullname %></td>
        <td>
          <% if !member.duty.nil? %>
            <%= member.duty %>
          <% else %>
            <%= 'No duty yet!' %>
          <% end %>
        </td>
        <td><%= member.user.email %></td>
        
        <% if @teammate_review_allowed %>
  
negative.code:                 remove_participant_student_teams_path(student_id: @student.id, team_id: @student.team.id) %>
    <% end %>
  
  <%# this part is temporaly disabled because the role-based reviewing feature needs to be re-done%>
  <% if false && @student.team != nil %>
    <h2>Team-member role (duty)</h2>
  
    <%=form_tag :controller=>'participants', :action=>'update_duties', :student_id=>@student.id do %>
  