<script type="text/template" id="xblock-attempts-template">
  <% if (_.isNumber(max_attempts) && max_attempts > 0) {{ %>
  <span> You have used <%= _.min([num_attempts, max_attempts]) %> of <%= max_attempts %> attempts.</span>
  <% }} %>
</script>

<script type="text/template" id="xblock-attempts-template">
  <% if (_.isNumber(max_attempts) && max_attempts > 0) {{ %>
  <span> You have used <%= _.min([num_attempts, max_attempts]) %> of <%= max_attempts %> submissions.</span>
  <% }} %>
</script>

Write 'submissions' instead of 'attempts'
Write 'submissions' instead of 'attempts'
