2.  Perfect in -i with Reduplication.

ab-do abdere abdidi abditus conceal
red-do red-dere reddidi redditus return
So addo, condo, dedo, perdo, prodo,
trado, etc.
con-sisto consistere constiti ——­ take one’s stand
resisto resistere restiti ——­ resist
circumsisto circumsistere circumsteti ——­ surround
cado cadere cecidi casurus fall
caedo caedere cecidi caesus kill
pendo pendere pependi pensus weigh, pay
tendo tendere tetendi tentus stretch
tundo tundere tutudi tusus, tunsus beat
fallo fallere fefelli (falsus, as deceive
Adj.)
pello pellere pepuli pulsus drive out
curro currere cucurri cursum (est) run
parco parcere peperci parsurus spare
cano canere cecini ——­ sing
tango tangere tetigi tactus touch
pungo pungere pupugi punctus prick

NOTE.—­In the following verbs the perfects were originally reduplicated, but have lost the reduplicating syllable:—­ per-cello percellere perculi perculsus strike down findo findere fidi fissus split scindo scindere scidi scissus tear apart tollo tollere sus-tuli sublatus remove

3.  Perfect in -i with Lengthening of Stem Vowel.

ago         agere       egi         actus            drive, do
perago    peragere    peregi      peractus         finish
subigo    subigere    subegi      subactus         subdue
cogo      cogere      coegi       coactus          force, gather
frango      frangere    fregi       fractus          break
perfringo  perfringere  perfregi  perfractus       break down
lego        legere      legi        lectus           gather, read
perlego   perlegere   perlegi     perlectus        read through
colligo   colligere   collegi     collectus        collect
deligo    deligere    delegi      delectus         choose
diligo    diligere    dilexi      dilectus         love
intellego  intellegere  intellexi  intellectus     understand
neglego   neglegere   neglexi     neglectus        neglect
emo         emere       emi         emptus           buy
coemo     coemere     coemi       coemptus         buy up
redimo    redimere    redemi      redemptus        buy back
dirimo    dirimere    diremi      diremptus        destroy