Why can't it be "they're learning biology"? I get that "apprendre" can also mean "to study", but not necessarily.
yeah you're right! It should be accepted
How can you tell from the audio that it is "il" or "ils"?!?!
There's liaison with "ils" and "apprennent" has a final "n" sound that "apprend" does not.
Il apprends vs il(z) apprennent. There is a z sound after ils if the next word starts with a vowel. Even if they do not pronounce the z, you wioo know it is "ils" because "apprennent" ends in an "n" sound while "apprends" does not.
How do I know when to use étudie form or apprennent?
Generally both "étudier" and "apprendre" are accepted for "to study".
Neither Collins nor Larousse dictionaries give "to study" as a translation for "apprendre." What version of French is duo offering?
I agree with you. There is a difference between learning and studying.