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