English verb conjugation
MUST TARIFF

Regular verb: tariff - tariffed - tariffed

Affirmation

Simple form	V-ing form
I must tariff you must tariff he must tariff we must tariff you must tariff they must tariff	I must be tariffing you must be tariffing he must be tariffing we must be tariffing you must be tariffing they must be tariffing
Perfect	V-ing perfect
I must have tariffed you must have tariffed he must have tariffed we must have tariffed you must have tariffed they must have tariffed	I must have been tariffing you must have been tariffing he must have been tariffing we must have been tariffing you must have been tariffing they must have been tariffing

Negation

Simple form	V-ing form
I mustn't tariff you mustn't tariff he mustn't tariff we mustn't tariff you mustn't tariff they mustn't tariff	I mustn't be tariffing you mustn't be tariffing he mustn't be tariffing we mustn't be tariffing you mustn't be tariffing they mustn't be tariffing
Perfect	V-ing perfect
I mustn't have tariffed you mustn't have tariffed he mustn't have tariffed we mustn't have tariffed you mustn't have tariffed they mustn't have tariffed	I mustn't have been tariffing you mustn't have been tariffing he mustn't have been tariffing we mustn't have been tariffing you mustn't have been tariffing they mustn't have been tariffing

Interrogative form

Simple form	V-ing form
must I tariff? must you tariff? must he tariff? must we tariff? must you tariff? must they tariff?	must I be tariffing? must you be tariffing? must he be tariffing? must we be tariffing? must you be tariffing? must they be tariffing?
Perfect	V-ing perfect
must I have tariffed? must you have tariffed? must he have tariffed? must we have tariffed? must you have tariffed? must they have tariffed?	must I have been tariffing? must you have been tariffing? must he have been tariffing? must we have been tariffing? must you have been tariffing? must they have been tariffing?

Interro-negative form

Simple form	V-ing form
mustn't I tariff? mustn't you tariff? mustn't he tariff? mustn't we tariff? mustn't you tariff? mustn't they tariff?	mustn't I be tariffing? mustn't you be tariffing? mustn't he be tariffing? mustn't we be tariffing? mustn't you be tariffing? mustn't they be tariffing?
Perfect	V-ing perfect
mustn't I have tariffed? mustn't you have tariffed? mustn't he have tariffed? mustn't we have tariffed? mustn't you have tariffed? mustn't they have tariffed?	mustn't I have been tariffing? mustn't you have been tariffing? mustn't he have been tariffing? mustn't we have been tariffing? mustn't you have been tariffing? mustn't they have been tariffing?