do I not prevent? do you not prevent? does he not prevent? do we not prevent? do you not prevent? do they not prevent?
Present continuous
am I not preventing? are you not preventing? is he not preventing? are we not preventing? are you not preventing? are they not preventing?
Preterite
did I not prevent? did you not prevent? did he not prevent? did we not prevent? did you not prevent? did they not prevent?
Preterite continuous
was I not preventing? were you not preventing? was he not preventing? were we not preventing? were you not preventing? were they not preventing?
Present perfect
have I not prevented? have you not prevented? has he not prevented? have we not prevented? have you not prevented? have they not prevented?
Present perfect continuous
have I not been preventing? have you not been preventing? has he not been preventing? have we not been preventing? have you not been preventing? have they not been preventing?
Pluperfect
had I not prevented? had you not prevented? had he not prevented? had we not prevented? had you not prevented? had they not prevented?
Pluperfect continuous
had I not been preventing? had you not been preventing? had he not been preventing? had we not been preventing? had you not been preventing? had they not been preventing?
Future
will I not prevent? will you not prevent? will he not prevent? will we not prevent? will you not prevent? will they not prevent?
Future continuous
will I not be preventing? will you not be preventing? will he not be preventing? will we not be preventing? will you not be preventing? will they not be preventing?
Future perfect
will I not have prevented? will you not have prevented? will he not have prevented? will we not have prevented? will you not have prevented? will they not have prevented?
Future perfect continuous
will I not have been preventing? will you not have been preventing? will he not have been preventing? will we not have been preventing? will you not have been preventing? will they not have been preventing?
Conditional
Present
would I not prevent? would you not prevent? would he not prevent? would we not prevent? would you not prevent? would they not prevent?
Present continuous
would I not be preventing? would you not be preventing? would he not be preventing? would we not be preventing? would you not be preventing? would they not be preventing?
Past
would I not have prevented? would you not have prevented? would he not have prevented? would we not have prevented? would you not have prevented? would they not have prevented?
Past continuous
would I not have been preventing? would you not have been preventing? would he not have been preventing? would we not have been preventing? would you not have been preventing? would they not have been preventing?