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