English verb conjugation
MUST SIP

Regular verb: sip - sipped - sipped

Affirmation

Simple form	V-ing form
I must sip you must sip he must sip we must sip you must sip they must sip	I must be sipping you must be sipping he must be sipping we must be sipping you must be sipping they must be sipping
Perfect	V-ing perfect
I must have sipped you must have sipped he must have sipped we must have sipped you must have sipped they must have sipped	I must have been sipping you must have been sipping he must have been sipping we must have been sipping you must have been sipping they must have been sipping

Negation

Simple form	V-ing form
I must not sip you must not sip he must not sip we must not sip you must not sip they must not sip	I must not be sipping you must not be sipping he must not be sipping we must not be sipping you must not be sipping they must not be sipping
Perfect	V-ing perfect
I must not have sipped you must not have sipped he must not have sipped we must not have sipped you must not have sipped they must not have sipped	I must not have been sipping you must not have been sipping he must not have been sipping we must not have been sipping you must not have been sipping they must not have been sipping

Interrogative form

Simple form	V-ing form
must I sip? must you sip? must he sip? must we sip? must you sip? must they sip?	must I be sipping? must you be sipping? must he be sipping? must we be sipping? must you be sipping? must they be sipping?
Perfect	V-ing perfect
must I have sipped? must you have sipped? must he have sipped? must we have sipped? must you have sipped? must they have sipped?	must I have been sipping? must you have been sipping? must he have been sipping? must we have been sipping? must you have been sipping? must they have been sipping?

Interro-negative form

Simple form	V-ing form
must I not sip? must you not sip? must he not sip? must we not sip? must you not sip? must they not sip?	must I not be sipping? must you not be sipping? must he not be sipping? must we not be sipping? must you not be sipping? must they not be sipping?
Perfect	V-ing perfect
must I not have sipped? must you not have sipped? must he not have sipped? must we not have sipped? must you not have sipped? must they not have sipped?	must I not have been sipping? must you not have been sipping? must he not have been sipping? must we not have been sipping? must you not have been sipping? must they not have been sipping?