I must interlock you must interlock she must interlock we must interlock you must interlock they must interlock
V-ing form
I must be interlocking you must be interlocking she must be interlocking we must be interlocking you must be interlocking they must be interlocking
Perfect
I must have interlocked you must have interlocked she must have interlocked we must have interlocked you must have interlocked they must have interlocked
V-ing perfect
I must have been interlocking you must have been interlocking she must have been interlocking we must have been interlocking you must have been interlocking they must have been interlocking
Negation
Simple form
I mustn't interlock you mustn't interlock she mustn't interlock we mustn't interlock you mustn't interlock they mustn't interlock
V-ing form
I mustn't be interlocking you mustn't be interlocking she mustn't be interlocking we mustn't be interlocking you mustn't be interlocking they mustn't be interlocking
Perfect
I mustn't have interlocked you mustn't have interlocked she mustn't have interlocked we mustn't have interlocked you mustn't have interlocked they mustn't have interlocked
V-ing perfect
I mustn't have been interlocking you mustn't have been interlocking she mustn't have been interlocking we mustn't have been interlocking you mustn't have been interlocking they mustn't have been interlocking
Interrogative form
Simple form
must I interlock? must you interlock? must she interlock? must we interlock? must you interlock? must they interlock?
V-ing form
must I be interlocking? must you be interlocking? must she be interlocking? must we be interlocking? must you be interlocking? must they be interlocking?
Perfect
must I have interlocked? must you have interlocked? must she have interlocked? must we have interlocked? must you have interlocked? must they have interlocked?
V-ing perfect
must I have been interlocking? must you have been interlocking? must she have been interlocking? must we have been interlocking? must you have been interlocking? must they have been interlocking?
Interro-negative form
Simple form
mustn't I interlock? mustn't you interlock? mustn't she interlock? mustn't we interlock? mustn't you interlock? mustn't they interlock?
V-ing form
mustn't I be interlocking? mustn't you be interlocking? mustn't she be interlocking? mustn't we be interlocking? mustn't you be interlocking? mustn't they be interlocking?
Perfect
mustn't I have interlocked? mustn't you have interlocked? mustn't she have interlocked? mustn't we have interlocked? mustn't you have interlocked? mustn't they have interlocked?
V-ing perfect
mustn't I have been interlocking? mustn't you have been interlocking? mustn't she have been interlocking? mustn't we have been interlocking? mustn't you have been interlocking? mustn't they have been interlocking?