English verb conjugation
MAY GRUB

Regular verb: grub - grubbed - grubbed

Affirmation

Simple form	V-ing form
I may grub you may grub he may grub we may grub you may grub they may grub	I may be grubbing you may be grubbing he may be grubbing we may be grubbing you may be grubbing they may be grubbing
Perfect	V-ing perfect
I may have grubbed you may have grubbed he may have grubbed we may have grubbed you may have grubbed they may have grubbed	I may have been grubbing you may have been grubbing he may have been grubbing we may have been grubbing you may have been grubbing they may have been grubbing

Negation

Simple form	V-ing form
I mayn't grub you mayn't grub he mayn't grub we mayn't grub you mayn't grub they mayn't grub	I mayn't be grubbing you mayn't be grubbing he mayn't be grubbing we mayn't be grubbing you mayn't be grubbing they mayn't be grubbing
Perfect	V-ing perfect
I mayn't have grubbed you mayn't have grubbed he mayn't have grubbed we mayn't have grubbed you mayn't have grubbed they mayn't have grubbed	I mayn't have been grubbing you mayn't have been grubbing he mayn't have been grubbing we mayn't have been grubbing you mayn't have been grubbing they mayn't have been grubbing

Interrogative form

Simple form	V-ing form
may I grub? may you grub? may he grub? may we grub? may you grub? may they grub?	may I be grubbing? may you be grubbing? may he be grubbing? may we be grubbing? may you be grubbing? may they be grubbing?
Perfect	V-ing perfect
may I have grubbed? may you have grubbed? may he have grubbed? may we have grubbed? may you have grubbed? may they have grubbed?	may I have been grubbing? may you have been grubbing? may he have been grubbing? may we have been grubbing? may you have been grubbing? may they have been grubbing?

Interro-negative form

Simple form	V-ing form
mayn't I grub? mayn't you grub? mayn't he grub? mayn't we grub? mayn't you grub? mayn't they grub?	mayn't I be grubbing? mayn't you be grubbing? mayn't he be grubbing? mayn't we be grubbing? mayn't you be grubbing? mayn't they be grubbing?
Perfect	V-ing perfect
mayn't I have grubbed? mayn't you have grubbed? mayn't he have grubbed? mayn't we have grubbed? mayn't you have grubbed? mayn't they have grubbed?	mayn't I have been grubbing? mayn't you have been grubbing? mayn't he have been grubbing? mayn't we have been grubbing? mayn't you have been grubbing? mayn't they have been grubbing?