I must describe you must describe he must describe we must describe you must describe they must describe
V-ing form
I must be describing you must be describing he must be describing we must be describing you must be describing they must be describing
Perfect
I must have described you must have described he must have described we must have described you must have described they must have described
V-ing perfect
I must have been describing you must have been describing he must have been describing we must have been describing you must have been describing they must have been describing
Negation
Simple form
I must not describe you must not describe he must not describe we must not describe you must not describe they must not describe
V-ing form
I must not be describing you must not be describing he must not be describing we must not be describing you must not be describing they must not be describing
Perfect
I must not have described you must not have described he must not have described we must not have described you must not have described they must not have described
V-ing perfect
I must not have been describing you must not have been describing he must not have been describing we must not have been describing you must not have been describing they must not have been describing
Interrogative form
Simple form
must I describe? must you describe? must he describe? must we describe? must you describe? must they describe?
V-ing form
must I be describing? must you be describing? must he be describing? must we be describing? must you be describing? must they be describing?
Perfect
must I have described? must you have described? must he have described? must we have described? must you have described? must they have described?
V-ing perfect
must I have been describing? must you have been describing? must he have been describing? must we have been describing? must you have been describing? must they have been describing?
Interro-negative form
Simple form
must I not describe? must you not describe? must he not describe? must we not describe? must you not describe? must they not describe?
V-ing form
must I not be describing? must you not be describing? must he not be describing? must we not be describing? must you not be describing? must they not be describing?
Perfect
must I not have described? must you not have described? must he not have described? must we not have described? must you not have described? must they not have described?
V-ing perfect
must I not have been describing? must you not have been describing? must he not have been describing? must we not have been describing? must you not have been describing? must they not have been describing?