Fatal error: The implementation option must be passed to the Sass task

[adeguntoro]

everytime i run : grunt monitor, i always get Sass task error. Why ?

Running "concurrent:monitor" (concurrent) task
    Running "sass:gh" (sass) task
    Running "watch:js" (watch) task
    Waiting...
    Running "notify:watching" (notify) task
    Running "browserSync:bsFiles" (browserSync) task
    Fatal error: The implementation option must be passed to the Sass task
    Running "watch:jade" (watch) task
    Waiting...
Warning:  Use --force to continue.

Aborted due to warnings.