I may trephine you may trephine he may trephine we may trephine you may trephine they may trephine
V-ing form
I may be trephining you may be trephining he may be trephining we may be trephining you may be trephining they may be trephining
Perfect
I may have trephined you may have trephined he may have trephined we may have trephined you may have trephined they may have trephined
V-ing perfect
I may have been trephining you may have been trephining he may have been trephining we may have been trephining you may have been trephining they may have been trephining
Negation
Simple form
I mayn't trephine you mayn't trephine he mayn't trephine we mayn't trephine you mayn't trephine they mayn't trephine
V-ing form
I mayn't be trephining you mayn't be trephining he mayn't be trephining we mayn't be trephining you mayn't be trephining they mayn't be trephining
Perfect
I mayn't have trephined you mayn't have trephined he mayn't have trephined we mayn't have trephined you mayn't have trephined they mayn't have trephined
V-ing perfect
I mayn't have been trephining you mayn't have been trephining he mayn't have been trephining we mayn't have been trephining you mayn't have been trephining they mayn't have been trephining
Interrogative form
Simple form
may I trephine? may you trephine? may he trephine? may we trephine? may you trephine? may they trephine?
V-ing form
may I be trephining? may you be trephining? may he be trephining? may we be trephining? may you be trephining? may they be trephining?
Perfect
may I have trephined? may you have trephined? may he have trephined? may we have trephined? may you have trephined? may they have trephined?
V-ing perfect
may I have been trephining? may you have been trephining? may he have been trephining? may we have been trephining? may you have been trephining? may they have been trephining?
Interro-negative form
Simple form
mayn't I trephine? mayn't you trephine? mayn't he trephine? mayn't we trephine? mayn't you trephine? mayn't they trephine?
V-ing form
mayn't I be trephining? mayn't you be trephining? mayn't he be trephining? mayn't we be trephining? mayn't you be trephining? mayn't they be trephining?
Perfect
mayn't I have trephined? mayn't you have trephined? mayn't he have trephined? mayn't we have trephined? mayn't you have trephined? mayn't they have trephined?
V-ing perfect
mayn't I have been trephining? mayn't you have been trephining? mayn't he have been trephining? mayn't we have been trephining? mayn't you have been trephining? mayn't they have been trephining?