I must chain-smoke you must chain-smoke she must chain-smoke we must chain-smoke you must chain-smoke they must chain-smoke
V-ing form
I must be chain-smoking you must be chain-smoking she must be chain-smoking we must be chain-smoking you must be chain-smoking they must be chain-smoking
Perfect
I must have chain-smoked you must have chain-smoked she must have chain-smoked we must have chain-smoked you must have chain-smoked they must have chain-smoked
V-ing perfect
I must have been chain-smoking you must have been chain-smoking she must have been chain-smoking we must have been chain-smoking you must have been chain-smoking they must have been chain-smoking
Negation
Simple form
I mustn't chain-smoke you mustn't chain-smoke she mustn't chain-smoke we mustn't chain-smoke you mustn't chain-smoke they mustn't chain-smoke
V-ing form
I mustn't be chain-smoking you mustn't be chain-smoking she mustn't be chain-smoking we mustn't be chain-smoking you mustn't be chain-smoking they mustn't be chain-smoking
Perfect
I mustn't have chain-smoked you mustn't have chain-smoked she mustn't have chain-smoked we mustn't have chain-smoked you mustn't have chain-smoked they mustn't have chain-smoked
V-ing perfect
I mustn't have been chain-smoking you mustn't have been chain-smoking she mustn't have been chain-smoking we mustn't have been chain-smoking you mustn't have been chain-smoking they mustn't have been chain-smoking
Interrogative form
Simple form
must I chain-smoke? must you chain-smoke? must she chain-smoke? must we chain-smoke? must you chain-smoke? must they chain-smoke?
V-ing form
must I be chain-smoking? must you be chain-smoking? must she be chain-smoking? must we be chain-smoking? must you be chain-smoking? must they be chain-smoking?
Perfect
must I have chain-smoked? must you have chain-smoked? must she have chain-smoked? must we have chain-smoked? must you have chain-smoked? must they have chain-smoked?
V-ing perfect
must I have been chain-smoking? must you have been chain-smoking? must she have been chain-smoking? must we have been chain-smoking? must you have been chain-smoking? must they have been chain-smoking?
Interro-negative form
Simple form
mustn't I chain-smoke? mustn't you chain-smoke? mustn't she chain-smoke? mustn't we chain-smoke? mustn't you chain-smoke? mustn't they chain-smoke?
V-ing form
mustn't I be chain-smoking? mustn't you be chain-smoking? mustn't she be chain-smoking? mustn't we be chain-smoking? mustn't you be chain-smoking? mustn't they be chain-smoking?
Perfect
mustn't I have chain-smoked? mustn't you have chain-smoked? mustn't she have chain-smoked? mustn't we have chain-smoked? mustn't you have chain-smoked? mustn't they have chain-smoked?
V-ing perfect
mustn't I have been chain-smoking? mustn't you have been chain-smoking? mustn't she have been chain-smoking? mustn't we have been chain-smoking? mustn't you have been chain-smoking? mustn't they have been chain-smoking?