Match each of these 3rd declension nouns with its correct gender. A brightly colored line will appear if you are correct. Since there are three choices for each, you may have to move the nouns around to see the line.
Masculine Gender
caupō
pēs
iānitor
Feminine Gender
nūbēs
pars
arbor
Neuter Gender
murmur
iter
tempus
Common (Masc. or Fem.)
parēns
cīvis
canis