English verb conjugation
MUST IMPROVE

Regular verb: improve - improved - improved

Affirmation

Simple form	V-ing form
I must improve you must improve he must improve we must improve you must improve they must improve	I must be improving you must be improving he must be improving we must be improving you must be improving they must be improving
Perfect	V-ing perfect
I must have improved you must have improved he must have improved we must have improved you must have improved they must have improved	I must have been improving you must have been improving he must have been improving we must have been improving you must have been improving they must have been improving

Negation

Simple form	V-ing form
I must not improve you must not improve he must not improve we must not improve you must not improve they must not improve	I must not be improving you must not be improving he must not be improving we must not be improving you must not be improving they must not be improving
Perfect	V-ing perfect
I must not have improved you must not have improved he must not have improved we must not have improved you must not have improved they must not have improved	I must not have been improving you must not have been improving he must not have been improving we must not have been improving you must not have been improving they must not have been improving

Interrogative form

Simple form	V-ing form
must I improve? must you improve? must he improve? must we improve? must you improve? must they improve?	must I be improving? must you be improving? must he be improving? must we be improving? must you be improving? must they be improving?
Perfect	V-ing perfect
must I have improved? must you have improved? must he have improved? must we have improved? must you have improved? must they have improved?	must I have been improving? must you have been improving? must he have been improving? must we have been improving? must you have been improving? must they have been improving?

Interro-negative form

Simple form	V-ing form
must I not improve? must you not improve? must he not improve? must we not improve? must you not improve? must they not improve?	must I not be improving? must you not be improving? must he not be improving? must we not be improving? must you not be improving? must they not be improving?
Perfect	V-ing perfect
must I not have improved? must you not have improved? must he not have improved? must we not have improved? must you not have improved? must they not have improved?	must I not have been improving? must you not have been improving? must he not have been improving? must we not have been improving? must you not have been improving? must they not have been improving?