infinitive

present

work up

indicative

present

(I)work up
(you)work up
(he,she,it)work s up
(we)work up
(you)work up
(they)work up

past

(I)work ed up
(you)work ed up
(he,she,it)work ed up
(we)work ed up
(you)work ed up
(they)work ed up

participle

present

work ing up

past

work ed up