I must appreciate you must appreciate he must appreciate we must appreciate you must appreciate they must appreciate
V-ing form
I must be appreciating you must be appreciating he must be appreciating we must be appreciating you must be appreciating they must be appreciating
Perfect
I must have appreciated you must have appreciated he must have appreciated we must have appreciated you must have appreciated they must have appreciated
V-ing perfect
I must have been appreciating you must have been appreciating he must have been appreciating we must have been appreciating you must have been appreciating they must have been appreciating
Negation
Simple form
I must not appreciate you must not appreciate he must not appreciate we must not appreciate you must not appreciate they must not appreciate
V-ing form
I must not be appreciating you must not be appreciating he must not be appreciating we must not be appreciating you must not be appreciating they must not be appreciating
Perfect
I must not have appreciated you must not have appreciated he must not have appreciated we must not have appreciated you must not have appreciated they must not have appreciated
V-ing perfect
I must not have been appreciating you must not have been appreciating he must not have been appreciating we must not have been appreciating you must not have been appreciating they must not have been appreciating
Interrogative form
Simple form
must I appreciate? must you appreciate? must he appreciate? must we appreciate? must you appreciate? must they appreciate?
V-ing form
must I be appreciating? must you be appreciating? must he be appreciating? must we be appreciating? must you be appreciating? must they be appreciating?
Perfect
must I have appreciated? must you have appreciated? must he have appreciated? must we have appreciated? must you have appreciated? must they have appreciated?
V-ing perfect
must I have been appreciating? must you have been appreciating? must he have been appreciating? must we have been appreciating? must you have been appreciating? must they have been appreciating?
Interro-negative form
Simple form
must I not appreciate? must you not appreciate? must he not appreciate? must we not appreciate? must you not appreciate? must they not appreciate?
V-ing form
must I not be appreciating? must you not be appreciating? must he not be appreciating? must we not be appreciating? must you not be appreciating? must they not be appreciating?
Perfect
must I not have appreciated? must you not have appreciated? must he not have appreciated? must we not have appreciated? must you not have appreciated? must they not have appreciated?
V-ing perfect
must I not have been appreciating? must you not have been appreciating? must he not have been appreciating? must we not have been appreciating? must you not have been appreciating? must they not have been appreciating?