must gamble
Regular verb: gamble - gambled- gambled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must gamble
you must gamble
he must gamble
we must gamble
you must gamble
they must gamble 	I must be gambling
you must be gambling
he must be gambling
we must be gambling
you must be gambling
they must be gambling	I must have gambled
you must have gambled
he must have gambled
we must have gambled
you must have gambled
they must have gambled	I must have been gambling
you must have been gambling
he must have been gambling
we must have been gambling
you must have been gambling
they must have been gambling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not gamble
you must not gamble
he must not gamble
we must not gamble
you must not gamble
they must not gamble 	I must not be gambling
you must not be gambling
he must not be gambling
we must not be gambling
you must not be gambling
they must not be gambling	I must not have gambled
you must not have gambled
he must not have gambled
we must not have gambled
you must not have gambled
they must not have gambled	I must not have been gambling
you must not have been gambling
he must not have been gambling
we must not have been gambling
you must not have been gambling
they must not have been gambling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I gamble?
must you gamble?
must he gamble?
must we gamble?
must you gamble?
must they gamble? 	must I be gambling?
must you be gambling?
must he be gambling?
must we be gambling?
must you be gambling?
must they be gambling? 	must I have gambled?
must you have gambled?
must he have gambled?
must we have gambled?
must you have gambled?
must they have gambled? 	must I have been gambling?
must you have been gambling?
must he have been gambling?
must we have been gambling?
must you have been gambling?
must they have been gambling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not gamble?
must you not gamble?
must he not gamble?
must we not gamble?
must you not gamble?
must they not gamble? 	must I not be gambling?
must you not be gambling?
must he not be gambling?
must we not be gambling?
must you not be gambling?
must they not be gambling? 	must I not have gambled?
must you not have gambled?
must he not have gambled?
must we not have gambled?
must you not have gambled?
must they not have gambled? 	must I not have been gambling?
must you not have been gambling?
must he not have been gambling?
must we not have been gambling?
must you not have been gambling?
must they not have been gambling?