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