disc-o, I learn; dŏce-o (doct-) I teach: disciple, docile, doctor, doct-rine.
do (dăt-), dōn-o (dōnāt-), I give, present: data, date, dative, donor, donate, add (= ad + do), render (Fr.; re-, back), dotal, dowry (Fr.), dowager.
dŏl-eo, I grieve; dŏl-or, grief, pain: dole (= grief), doleful, dolor, dolorous, condole, in-dolent.
dŏm-o (dŏmĭt-) I subdue; dŏmin-us, lord, master: in-domitable, dominant.
dŏm-us, house: domestic, domicile.
dormi-o (dormīt-), I sleep: dormitory, dormant and dormer (Fr.).
duc- lead—duc-o (dŭct-); ēdŭc-o (educāt-), I rear; dux (dŭc-), leader: re-duce, ductile, conduct, conduit (Fr.), deduction, traduce, education.
duo, two: dual, duel (see [bellum]), double (Fr.; duplus), doublet, duplex.
Ĕm-o (empt-), I buy; ex-emp-lum, example: pre-empt, ex-emption, exemplify, per-emptory, sample (Fr.), redeem, ransom (Fr.; red-imo).