Regular verb: research - researched - researched
Simple form | V-ing form |
I must research you must research he must research we must research you must research they must research | I must be researching you must be researching he must be researching we must be researching you must be researching they must be researching |
Perfect | V-ing perfect |
I must have researched you must have researched he must have researched we must have researched you must have researched they must have researched | I must have been researching you must have been researching he must have been researching we must have been researching you must have been researching they must have been researching |
Simple form | V-ing form |
I must not research you must not research he must not research we must not research you must not research they must not research | I must not be researching you must not be researching he must not be researching we must not be researching you must not be researching they must not be researching |
Perfect | V-ing perfect |
I must not have researched you must not have researched he must not have researched we must not have researched you must not have researched they must not have researched | I must not have been researching you must not have been researching he must not have been researching we must not have been researching you must not have been researching they must not have been researching |
Simple form | V-ing form |
must I research? must you research? must he research? must we research? must you research? must they research? | must I be researching? must you be researching? must he be researching? must we be researching? must you be researching? must they be researching? |
Perfect | V-ing perfect |
must I have researched? must you have researched? must he have researched? must we have researched? must you have researched? must they have researched? | must I have been researching? must you have been researching? must he have been researching? must we have been researching? must you have been researching? must they have been researching? |
Simple form | V-ing form |
must I not research? must you not research? must he not research? must we not research? must you not research? must they not research? | must I not be researching? must you not be researching? must he not be researching? must we not be researching? must you not be researching? must they not be researching? |
Perfect | V-ing perfect |
must I not have researched? must you not have researched? must he not have researched? must we not have researched? must you not have researched? must they not have researched? | must I not have been researching? must you not have been researching? must he not have been researching? must we not have been researching? must you not have been researching? must they not have been researching? |