English verb conjugation
MAY LACK

Regular verb: lack - lacked - lacked

Affirmation

Simple form	V-ing form
I may lack you may lack she may lack we may lack you may lack they may lack	I may be lacking you may be lacking she may be lacking we may be lacking you may be lacking they may be lacking
Perfect	V-ing perfect
I may have lacked you may have lacked she may have lacked we may have lacked you may have lacked they may have lacked	I may have been lacking you may have been lacking she may have been lacking we may have been lacking you may have been lacking they may have been lacking

Negation

Simple form	V-ing form
I may not lack you may not lack she may not lack we may not lack you may not lack they may not lack	I may not be lacking you may not be lacking she may not be lacking we may not be lacking you may not be lacking they may not be lacking
Perfect	V-ing perfect
I may not have lacked you may not have lacked she may not have lacked we may not have lacked you may not have lacked they may not have lacked	I may not have been lacking you may not have been lacking she may not have been lacking we may not have been lacking you may not have been lacking they may not have been lacking

Interrogative form

Simple form	V-ing form
may I lack? may you lack? may she lack? may we lack? may you lack? may they lack?	may I be lacking? may you be lacking? may she be lacking? may we be lacking? may you be lacking? may they be lacking?
Perfect	V-ing perfect
may I have lacked? may you have lacked? may she have lacked? may we have lacked? may you have lacked? may they have lacked?	may I have been lacking? may you have been lacking? may she have been lacking? may we have been lacking? may you have been lacking? may they have been lacking?

Interro-negative form

Simple form	V-ing form
may I not lack? may you not lack? may she not lack? may we not lack? may you not lack? may they not lack?	may I not be lacking? may you not be lacking? may she not be lacking? may we not be lacking? may you not be lacking? may they not be lacking?
Perfect	V-ing perfect
may I not have lacked? may you not have lacked? may she not have lacked? may we not have lacked? may you not have lacked? may they not have lacked?	may I not have been lacking? may you not have been lacking? may she not have been lacking? may we not have been lacking? may you not have been lacking? may they not have been lacking?