Asked as someone learning Portuguese (European). Findings drawn from Portuguese (European)-specific research are framed for Portuguese (European) learners and may not hold for other languages; where the evidence is general second-language research, the report says so.
The sources don't address European Portuguese or Dutch speakers specifically, but general second-language research consistently supports a clear priority for someone in your position: start speaking now (it's the skill most improved by actual practice, not passive input), keep building writing through regular practice and feedback, and balance your year across input, focused language study, real communicative output, and fluency drills rather than over-relying on any one mode. A year is plausible for real gains, but expect faster progress early on and more gradual gains later.
Across several studies, learners' spoken/oral skills improved specifically when they had structured opportunities to actually produce speech (not just listen or read) — for example through picture-book conversations, podcasts, or interactive tasks. Since you say you haven't started speaking at all, this is likely your biggest gap to close for B2, and starting it early rather than late matters.3,4,12
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A study comparing English learners across four proficiency levels found that grammatical development (the order in which grammar structures are mastered) is very similar whether you're speaking or writing, but accuracy is reached earlier and stays more stable in writing than in speaking. This fits your situation: your writing (A2) may lag behind your understanding (B1) simply because writing accuracy takes deliberate practice, while your speaking, once you begin, may initially be less accurate and less stable than your writing until you get more practice.2
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A large study of Dutch-speaking children learning English out of school found that the most effective activities for gaining proficiency involved interactive, multimodal engagement that required actually producing language — like gaming, social media use, and speaking — rather than passive input alone.7
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An action-research study found that when learners were given meaningful, low-pressure speaking and writing tasks (rather than drills focused just on grammatical correctness), their fluency scores rose substantially and their writing errors dropped, alongside a visible boost in confidence.4
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In one study of low-proficiency students doing tasks that combined listening, reading, and writing together, independent skill scores in each of those areas explained less than a third of how well students did on the combined task — meaning practicing these skills separately doesn't automatically transfer to using them together, and writing practice specifically had the strongest link to combined performance, while reading's contribution was surprisingly weak.11
Multiple studies found that AI-assisted writing feedback (e.g. via ChatGPT or Grammarly-type tools) led to measurable gains in learners' writing skill and motivation, and in one direct comparison, AI feedback performed about as well as feedback from a human tutor.1,5,6
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A study of adult immigrants learning English found that the longer they had lived and used the language daily, the better their pronunciation and overall spoken comprehensibility became, but improvement was much faster in the first months and slower afterward — meaning consistent, ongoing use matters more than any single technique, and plateauing is normal, not a sign something is wrong.8
One teaching framework described in the sources breaks study into four connected strands: understandable input (listening/reading), focused grammar/vocabulary study, meaningful output (speaking/writing), and dedicated fluency practice — with the recommendation that all four be balanced rather than over-relying on just one.9,10
In plain terms
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