MASCULINE: un băiat - doi băieți
- M. SG. | băiatul acela/ăla = that boy
- M. PL. | băieții aceia/ăia = those boys
FEMININE: o fată - două fete
- F. SG. | fata aceea/aia = that girl
- F. PL. | fetele acelea/ălea = those girls
NEUTER: un fruct - două fructe
- N. SG. | fructul acela/ăla = that fruit
- N. PL. | fructele acelea/ălea = those fruits
N. SG. = M. SG.
N. PL. = F. PL.
The short version (what is written after "/") is not used in writing.
M. - masculine, F. - feminine, N. - neuter, SG. - singular, PL. - plural
My understanding of fruit in English is like fish: multiple fruit of a particular type are "fruit". Multiple fish of a type are "fish". However, multiple species of fruit are "fruits" and multiple species of fish are "fishes" (this latter in particular is essentially unknown outside of academic use).
Does fructele refer specifically to different types of fruit, or is it simply multiple fruit? If it can be the latter, then "those fruit" should be accepted I think.
There is no "alea" in the Notes: https://www.duolingo.com/skill/ro/Demonstrative-Pronouns-and-Pronominal-Adjectives/tips-and-notes