An user French
says…

En retour
les
Determiner
  vassaux
Noun
  devaient
Verb
  rendre
Verb
  certains
Determiner
  services
Noun
  à
Adposition
  leur
Determiner
  hôte
Noun
.

In return, the vassals had to render certain services to their host.
Words and sentences
New
en retour

in return, in exchange, in turn, back

New
les

New
devaient

third-person plural imperfect indicative of devoir

New
rendre

  1. to give back
  2. to give back
  3. to render
  4. to render
  5. to render
  6. to render
  7. to pay (a visit, respects)
  8. to yield
  9. to vomit, to let out from the body
  10. to render oneself, to make oneself, to become due to one's actions
  11. to make one's way (to a place), to get oneself (into a place)
  12. to call on (someone)
  13. to surrender, to give in, to give oneself up to

New
certains

New
services

plural of service

New
leur

New
hôte

  1. guest (one who is received)
  2. host (one who receives)
  3. host (being that carries a parasite)

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