Regular verb: stumble - stumbled - stumbled
Simple form | V-ing form |
I must stumble you must stumble he must stumble we must stumble you must stumble they must stumble | I must be stumbling you must be stumbling he must be stumbling we must be stumbling you must be stumbling they must be stumbling |
Perfect | V-ing perfect |
I must have stumbled you must have stumbled he must have stumbled we must have stumbled you must have stumbled they must have stumbled | I must have been stumbling you must have been stumbling he must have been stumbling we must have been stumbling you must have been stumbling they must have been stumbling |
Simple form | V-ing form |
I must not stumble you must not stumble he must not stumble we must not stumble you must not stumble they must not stumble | I must not be stumbling you must not be stumbling he must not be stumbling we must not be stumbling you must not be stumbling they must not be stumbling |
Perfect | V-ing perfect |
I must not have stumbled you must not have stumbled he must not have stumbled we must not have stumbled you must not have stumbled they must not have stumbled | I must not have been stumbling you must not have been stumbling he must not have been stumbling we must not have been stumbling you must not have been stumbling they must not have been stumbling |
Simple form | V-ing form |
must I stumble? must you stumble? must he stumble? must we stumble? must you stumble? must they stumble? | must I be stumbling? must you be stumbling? must he be stumbling? must we be stumbling? must you be stumbling? must they be stumbling? |
Perfect | V-ing perfect |
must I have stumbled? must you have stumbled? must he have stumbled? must we have stumbled? must you have stumbled? must they have stumbled? | must I have been stumbling? must you have been stumbling? must he have been stumbling? must we have been stumbling? must you have been stumbling? must they have been stumbling? |
Simple form | V-ing form |
must I not stumble? must you not stumble? must he not stumble? must we not stumble? must you not stumble? must they not stumble? | must I not be stumbling? must you not be stumbling? must he not be stumbling? must we not be stumbling? must you not be stumbling? must they not be stumbling? |
Perfect | V-ing perfect |
must I not have stumbled? must you not have stumbled? must he not have stumbled? must we not have stumbled? must you not have stumbled? must they not have stumbled? | must I not have been stumbling? must you not have been stumbling? must he not have been stumbling? must we not have been stumbling? must you not have been stumbling? must they not have been stumbling? |