I must travel you must travel she must travel we must travel you must travel they must travel
V-ing form
I must be travelling you must be travelling she must be travelling we must be travelling you must be travelling they must be travelling
Perfect
I must have travelled you must have travelled she must have travelled we must have travelled you must have travelled they must have travelled
V-ing perfect
I must have been travelling you must have been travelling she must have been travelling we must have been travelling you must have been travelling they must have been travelling
Negation
Simple form
I must not travel you must not travel she must not travel we must not travel you must not travel they must not travel
V-ing form
I must not be travelling you must not be travelling she must not be travelling we must not be travelling you must not be travelling they must not be travelling
Perfect
I must not have travelled you must not have travelled she must not have travelled we must not have travelled you must not have travelled they must not have travelled
V-ing perfect
I must not have been travelling you must not have been travelling she must not have been travelling we must not have been travelling you must not have been travelling they must not have been travelling
Interrogative form
Simple form
must I travel? must you travel? must she travel? must we travel? must you travel? must they travel?
V-ing form
must I be travelling? must you be travelling? must she be travelling? must we be travelling? must you be travelling? must they be travelling?
Perfect
must I have travelled? must you have travelled? must she have travelled? must we have travelled? must you have travelled? must they have travelled?
V-ing perfect
must I have been travelling? must you have been travelling? must she have been travelling? must we have been travelling? must you have been travelling? must they have been travelling?
Interro-negative form
Simple form
must I not travel? must you not travel? must she not travel? must we not travel? must you not travel? must they not travel?
V-ing form
must I not be travelling? must you not be travelling? must she not be travelling? must we not be travelling? must you not be travelling? must they not be travelling?
Perfect
must I not have travelled? must you not have travelled? must she not have travelled? must we not have travelled? must you not have travelled? must they not have travelled?
V-ing perfect
must I not have been travelling? must you not have been travelling? must she not have been travelling? must we not have been travelling? must you not have been travelling? must they not have been travelling?