I may fasten you may fasten she may fasten we may fasten you may fasten they may fasten
V-ing form
I may be fastening you may be fastening she may be fastening we may be fastening you may be fastening they may be fastening
Perfect
I may have fastened you may have fastened she may have fastened we may have fastened you may have fastened they may have fastened
V-ing perfect
I may have been fastening you may have been fastening she may have been fastening we may have been fastening you may have been fastening they may have been fastening
Negation
Simple form
I may not fasten you may not fasten she may not fasten we may not fasten you may not fasten they may not fasten
V-ing form
I may not be fastening you may not be fastening she may not be fastening we may not be fastening you may not be fastening they may not be fastening
Perfect
I may not have fastened you may not have fastened she may not have fastened we may not have fastened you may not have fastened they may not have fastened
V-ing perfect
I may not have been fastening you may not have been fastening she may not have been fastening we may not have been fastening you may not have been fastening they may not have been fastening
Interrogative form
Simple form
may I fasten? may you fasten? may she fasten? may we fasten? may you fasten? may they fasten?
V-ing form
may I be fastening? may you be fastening? may she be fastening? may we be fastening? may you be fastening? may they be fastening?
Perfect
may I have fastened? may you have fastened? may she have fastened? may we have fastened? may you have fastened? may they have fastened?
V-ing perfect
may I have been fastening? may you have been fastening? may she have been fastening? may we have been fastening? may you have been fastening? may they have been fastening?
Interro-negative form
Simple form
may I not fasten? may you not fasten? may she not fasten? may we not fasten? may you not fasten? may they not fasten?
V-ing form
may I not be fastening? may you not be fastening? may she not be fastening? may we not be fastening? may you not be fastening? may they not be fastening?
Perfect
may I not have fastened? may you not have fastened? may she not have fastened? may we not have fastened? may you not have fastened? may they not have fastened?
V-ing perfect
may I not have been fastening? may you not have been fastening? may she not have been fastening? may we not have been fastening? may you not have been fastening? may they not have been fastening?