Warning, this verb may not exist. Conjugation is given as example.
Affirmation
Simple form
I must grub. nuzzle you must grub. nuzzle he must grub. nuzzle we must grub. nuzzle you must grub. nuzzle they must grub. nuzzle
V-ing form
I must be grub. nuzzling you must be grub. nuzzling he must be grub. nuzzling we must be grub. nuzzling you must be grub. nuzzling they must be grub. nuzzling
Perfect
I must have grub. nuzzled you must have grub. nuzzled he must have grub. nuzzled we must have grub. nuzzled you must have grub. nuzzled they must have grub. nuzzled
V-ing perfect
I must have been grub. nuzzling you must have been grub. nuzzling he must have been grub. nuzzling we must have been grub. nuzzling you must have been grub. nuzzling they must have been grub. nuzzling
Negation
Simple form
I must not grub. nuzzle you must not grub. nuzzle he must not grub. nuzzle we must not grub. nuzzle you must not grub. nuzzle they must not grub. nuzzle
V-ing form
I must not be grub. nuzzling you must not be grub. nuzzling he must not be grub. nuzzling we must not be grub. nuzzling you must not be grub. nuzzling they must not be grub. nuzzling
Perfect
I must not have grub. nuzzled you must not have grub. nuzzled he must not have grub. nuzzled we must not have grub. nuzzled you must not have grub. nuzzled they must not have grub. nuzzled
V-ing perfect
I must not have been grub. nuzzling you must not have been grub. nuzzling he must not have been grub. nuzzling we must not have been grub. nuzzling you must not have been grub. nuzzling they must not have been grub. nuzzling
Interrogative form
Simple form
must I grub. nuzzle? must you grub. nuzzle? must he grub. nuzzle? must we grub. nuzzle? must you grub. nuzzle? must they grub. nuzzle?
V-ing form
must I be grub. nuzzling? must you be grub. nuzzling? must he be grub. nuzzling? must we be grub. nuzzling? must you be grub. nuzzling? must they be grub. nuzzling?
Perfect
must I have grub. nuzzled? must you have grub. nuzzled? must he have grub. nuzzled? must we have grub. nuzzled? must you have grub. nuzzled? must they have grub. nuzzled?
V-ing perfect
must I have been grub. nuzzling? must you have been grub. nuzzling? must he have been grub. nuzzling? must we have been grub. nuzzling? must you have been grub. nuzzling? must they have been grub. nuzzling?
Interro-negative form
Simple form
must I not grub. nuzzle? must you not grub. nuzzle? must he not grub. nuzzle? must we not grub. nuzzle? must you not grub. nuzzle? must they not grub. nuzzle?
V-ing form
must I not be grub. nuzzling? must you not be grub. nuzzling? must he not be grub. nuzzling? must we not be grub. nuzzling? must you not be grub. nuzzling? must they not be grub. nuzzling?
Perfect
must I not have grub. nuzzled? must you not have grub. nuzzled? must he not have grub. nuzzled? must we not have grub. nuzzled? must you not have grub. nuzzled? must they not have grub. nuzzled?
V-ing perfect
must I not have been grub. nuzzling? must you not have been grub. nuzzling? must he not have been grub. nuzzling? must we not have been grub. nuzzling? must you not have been grub. nuzzling? must they not have been grub. nuzzling?