Regular verb: backcross - backcrossed - backcrossed
Simple form | V-ing form |
I must backcross you must backcross he must backcross we must backcross you must backcross they must backcross | I must be backcrossing you must be backcrossing he must be backcrossing we must be backcrossing you must be backcrossing they must be backcrossing |
Perfect | V-ing perfect |
I must have backcrossed you must have backcrossed he must have backcrossed we must have backcrossed you must have backcrossed they must have backcrossed | I must have been backcrossing you must have been backcrossing he must have been backcrossing we must have been backcrossing you must have been backcrossing they must have been backcrossing |
Simple form | V-ing form |
I must not backcross you must not backcross he must not backcross we must not backcross you must not backcross they must not backcross | I must not be backcrossing you must not be backcrossing he must not be backcrossing we must not be backcrossing you must not be backcrossing they must not be backcrossing |
Perfect | V-ing perfect |
I must not have backcrossed you must not have backcrossed he must not have backcrossed we must not have backcrossed you must not have backcrossed they must not have backcrossed | I must not have been backcrossing you must not have been backcrossing he must not have been backcrossing we must not have been backcrossing you must not have been backcrossing they must not have been backcrossing |
Simple form | V-ing form |
must I backcross? must you backcross? must he backcross? must we backcross? must you backcross? must they backcross? | must I be backcrossing? must you be backcrossing? must he be backcrossing? must we be backcrossing? must you be backcrossing? must they be backcrossing? |
Perfect | V-ing perfect |
must I have backcrossed? must you have backcrossed? must he have backcrossed? must we have backcrossed? must you have backcrossed? must they have backcrossed? | must I have been backcrossing? must you have been backcrossing? must he have been backcrossing? must we have been backcrossing? must you have been backcrossing? must they have been backcrossing? |
Simple form | V-ing form |
must I not backcross? must you not backcross? must he not backcross? must we not backcross? must you not backcross? must they not backcross? | must I not be backcrossing? must you not be backcrossing? must he not be backcrossing? must we not be backcrossing? must you not be backcrossing? must they not be backcrossing? |
Perfect | V-ing perfect |
must I not have backcrossed? must you not have backcrossed? must he not have backcrossed? must we not have backcrossed? must you not have backcrossed? must they not have backcrossed? | must I not have been backcrossing? must you not have been backcrossing? must he not have been backcrossing? must we not have been backcrossing? must you not have been backcrossing? must they not have been backcrossing? |