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 must not interlock you must not interlock she must not interlock we must not interlock you must not interlock they must not interlock
V-ing form
I must not be interlocking you must not be interlocking she must not be interlocking we must not be interlocking you must not be interlocking they must not be interlocking
Perfect
I must not have interlocked you must not have interlocked she must not have interlocked we must not have interlocked you must not have interlocked they must not have interlocked
V-ing perfect
I must not have been interlocking you must not have been interlocking she must not have been interlocking we must not have been interlocking you must not have been interlocking they must not 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
must I not interlock? must you not interlock? must she not interlock? must we not interlock? must you not interlock? must they not interlock?
V-ing form
must I not be interlocking? must you not be interlocking? must she not be interlocking? must we not be interlocking? must you not be interlocking? must they not be interlocking?
Perfect
must I not have interlocked? must you not have interlocked? must she not have interlocked? must we not have interlocked? must you not have interlocked? must they not have interlocked?
V-ing perfect
must I not have been interlocking? must you not have been interlocking? must she not have been interlocking? must we not have been interlocking? must you not have been interlocking? must they not have been interlocking?