Regular verb: concern - concerned - concerned
Simple form | V-ing form |
I must concern you must concern he must concern we must concern you must concern they must concern | I must be concerning you must be concerning he must be concerning we must be concerning you must be concerning they must be concerning |
Perfect | V-ing perfect |
I must have concerned you must have concerned he must have concerned we must have concerned you must have concerned they must have concerned | I must have been concerning you must have been concerning he must have been concerning we must have been concerning you must have been concerning they must have been concerning |
Simple form | V-ing form |
I mustn't concern you mustn't concern he mustn't concern we mustn't concern you mustn't concern they mustn't concern | I mustn't be concerning you mustn't be concerning he mustn't be concerning we mustn't be concerning you mustn't be concerning they mustn't be concerning |
Perfect | V-ing perfect |
I mustn't have concerned you mustn't have concerned he mustn't have concerned we mustn't have concerned you mustn't have concerned they mustn't have concerned | I mustn't have been concerning you mustn't have been concerning he mustn't have been concerning we mustn't have been concerning you mustn't have been concerning they mustn't have been concerning |
Simple form | V-ing form |
must I concern? must you concern? must he concern? must we concern? must you concern? must they concern? | must I be concerning? must you be concerning? must he be concerning? must we be concerning? must you be concerning? must they be concerning? |
Perfect | V-ing perfect |
must I have concerned? must you have concerned? must he have concerned? must we have concerned? must you have concerned? must they have concerned? | must I have been concerning? must you have been concerning? must he have been concerning? must we have been concerning? must you have been concerning? must they have been concerning? |
Simple form | V-ing form |
mustn't I concern? mustn't you concern? mustn't he concern? mustn't we concern? mustn't you concern? mustn't they concern? | mustn't I be concerning? mustn't you be concerning? mustn't he be concerning? mustn't we be concerning? mustn't you be concerning? mustn't they be concerning? |
Perfect | V-ing perfect |
mustn't I have concerned? mustn't you have concerned? mustn't he have concerned? mustn't we have concerned? mustn't you have concerned? mustn't they have concerned? | mustn't I have been concerning? mustn't you have been concerning? mustn't he have been concerning? mustn't we have been concerning? mustn't you have been concerning? mustn't they have been concerning? |