how can you learn a language without duolingo?
a tutor, a conversation partner, books written for learners, films and series with the words on screen, and audio you can follow: each of these can do part of what duolingo does, and some of what it does not. none of them is a single replacement. the useful question is which part of the language you want to work on next, because each alternative is strong in a different place. a sensible way to move on is to choose two: one that makes you produce the language, and one that gives you a lot of it to take in.

what duolingo does well
it is worth being fair to the thing you are leaving. in a study published in 2021 in the journal foreign language annals, a team of researchers, four of them employed by duolingo and one at northern arizona university, tested 225 adults in the united states who had finished duolingo's beginning spanish or french course, had little or no earlier knowledge of the language, and had used nothing else. they reached the levels the american council on the teaching of foreign languages calls intermediate low in reading and novice high in listening. in both skills, their scores were comparable with those of university students at the end of the fourth semester of study. only reading and listening were tested.
the app has also added more listening over time. its own blog describes audio exercises from the start of each unit, with more of them losing the written words as you go on, and short audio-only episodes built into the path in several of its courses.
so leaving does not have to mean the app failed you. it can mean you want what it does not test, such as holding a conversation, or that you want the language to come from somewhere other than an exercise. those are good reasons, and they point to different places.
someone who answers back
what a person gives you that an exercise does not is a reply you cannot predict. a paid tutor gives you that with structure: someone who notices your mistakes, chooses what to work on and makes you speak for an hour. a conversation exchange gives it to you for free, in return for helping someone else with your language, though with less structure and a partner who is not trained to teach.
researchers who study conversation in second languages, notably susan gass and alison mackey, describe what it adds in plain terms. talking with someone lets you notice the gap between how you put something and how they would, and their responses push you to say it again, better. that is the strongest reason to add a person: you get told, in the moment, what you could not have found by yourself.
the cost is real too. a tutor costs money, an exchange costs time and nerve, and both need a fixed slot in the week. if speaking is the part you most want, they are worth the cost, and if it is not yet, they can wait.
a lot of easy reading
graded readers are books written or simplified for learners, with a controlled vocabulary at each stage. reading many of them quickly, for the story, is what teachers call extensive reading. a 2014 analysis by takayuki nakanishi pooled 34 studies with nearly four thousand participants and found a medium-sized benefit to reading ability for learners who read this way compared with those who did not. it suits people who already like reading and who want vocabulary to grow without drilling it. it does little directly for speaking or for the speed of the spoken language.
the words on screen
films and series are a separate subject, and there is a whole article on them in this series. the short version: subtitles in the language you are learning help. a 2013 study by maribel montero perez, elke peters and piet desmet showed french clips to 226 flemish university students, and those who had full captions in french understood the gist better than those with none, or with only keywords captioned. it suits people who already watch a lot and can swap their usual subtitles for the language's own.
audio you can follow
listening material comes in three broad kinds, each doing a different job. podcasts made for learners, with a host who explains and slows down, are free in many languages and good for the commute. audio courses that pause and ask you to answer aloud build speaking without a screen. and bilingual audio, where each line comes with its translation, gives you the sound of the language with its meaning attached, without asking you to answer.
none of these needs a desk, which is their main advantage, and most of them cannot tell you what you got wrong, which is their main limit, and the reason they pair well with a person, who can.
choosing two
start from what you want to be able to do in six months, not from the method. if it is talking, take a tutor or an exchange and add audio for the rest of the week. if it is reading, take graded readers and add a series with captions. if it is understanding people when they speak, take listening material you can follow and a film you can rewatch.
then give it a month and ask one plain question: which skill moved? if the answer is none, change one of the two, not both, so you can tell what made the difference.
a different kind of listening
driftspeak is one of the listening options on this map, and it is not a course. it is subtitles for your ears: lines from albums and films, a line at a time, in their language and then in yours. words i kept, free in full in the app, has thirteen short tracks of lines kept from records and films on the shelf, about nineteen minutes in all, across eight languages. it asks nothing of you except to listen, which makes it a partner for a tutor or a book rather than a stand-in for either.
to hear the bilingual kind of listening before you choose, listen to a sample of words i kept and notice which of the three languages in its samples you want more of.