do I prevent? do you prevent? does he prevent? do we prevent? do you prevent? do they prevent?
Present continuous
am I preventing? are you preventing? is he preventing? are we preventing? are you preventing? are they preventing?
Preterite
did I prevent? did you prevent? did he prevent? did we prevent? did you prevent? did they prevent?
Preterite continuous
was I preventing? were you preventing? was he preventing? were we preventing? were you preventing? were they preventing?
Present perfect
have I prevented? have you prevented? has he prevented? have we prevented? have you prevented? have they prevented?
Present perfect continuous
have I been preventing? have you been preventing? has he been preventing? have we been preventing? have you been preventing? have they been preventing?
Pluperfect
had I prevented? had you prevented? had he prevented? had we prevented? had you prevented? had they prevented?
Pluperfect continuous
had I been preventing? had you been preventing? had he been preventing? had we been preventing? had you been preventing? had they been preventing?
Future
will I prevent? will you prevent? will he prevent? will we prevent? will you prevent? will they prevent?
Future continuous
will I be preventing? will you be preventing? will he be preventing? will we be preventing? will you be preventing? will they be preventing?
Future perfect
will I have prevented? will you have prevented? will he have prevented? will we have prevented? will you have prevented? will they have prevented?
Future perfect continuous
will I have been preventing? will you have been preventing? will he have been preventing? will we have been preventing? will you have been preventing? will they have been preventing?
Conditional
Present
would I prevent? would you prevent? would he prevent? would we prevent? would you prevent? would they prevent?
Present continuous
would I be preventing? would you be preventing? would he be preventing? would we be preventing? would you be preventing? would they be preventing?
Past
would I have prevented? would you have prevented? would he have prevented? would we have prevented? would you have prevented? would they have prevented?
Past continuous
would I have been preventing? would you have been preventing? would he have been preventing? would we have been preventing? would you have been preventing? would they have been preventing?