must speculate
Regular verb: speculate - speculated- speculated

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must speculate
you must speculate
she must speculate
we must speculate
you must speculate
they must speculate 	I must be speculating
you must be speculating
she must be speculating
we must be speculating
you must be speculating
they must be speculating	I must have speculated
you must have speculated
she must have speculated
we must have speculated
you must have speculated
they must have speculated	I must have been speculating
you must have been speculating
she must have been speculating
we must have been speculating
you must have been speculating
they must have been speculating	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't speculate
you mustn't speculate
she mustn't speculate
we mustn't speculate
you mustn't speculate
they mustn't speculate 	I mustn't be speculating
you mustn't be speculating
she mustn't be speculating
we mustn't be speculating
you mustn't be speculating
they mustn't be speculating	I mustn't have speculated
you mustn't have speculated
she mustn't have speculated
we mustn't have speculated
you mustn't have speculated
they mustn't have speculated	I mustn't have been speculating
you mustn't have been speculating
she mustn't have been speculating
we mustn't have been speculating
you mustn't have been speculating
they mustn't have been speculating	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I speculate?
must you speculate?
must she speculate?
must we speculate?
must you speculate?
must they speculate? 	must I be speculating?
must you be speculating?
must she be speculating?
must we be speculating?
must you be speculating?
must they be speculating? 	must I have speculated?
must you have speculated?
must she have speculated?
must we have speculated?
must you have speculated?
must they have speculated? 	must I have been speculating?
must you have been speculating?
must she have been speculating?
must we have been speculating?
must you have been speculating?
must they have been speculating? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I speculate?
mustn't you speculate?
mustn't she speculate?
mustn't we speculate?
mustn't you speculate?
mustn't they speculate? 	mustn't I be speculating?
mustn't you be speculating?
mustn't she be speculating?
mustn't we be speculating?
mustn't you be speculating?
mustn't they be speculating? 	mustn't I have speculated?
mustn't you have speculated?
mustn't she have speculated?
mustn't we have speculated?
mustn't you have speculated?
mustn't they have speculated? 	mustn't I have been speculating?
mustn't you have been speculating?
mustn't she have been speculating?
mustn't we have been speculating?
mustn't you have been speculating?
mustn't they have been speculating?