You know the words but nothing comes out. Why input and output are different skills.
What you build through reading and listening does not transfer to speaking on its own. There is a wide gap between what you can understand and what you can produce, and only producing closes it. That gap explains high test scores alongside a stalled conversation.
Assembling sentences from individual words costs time on every attempt. Native speakers mostly retrieve whole ready-made phrases. Memorising blocks such as 'it might be better to' or 'that depends on the situation' removes the assembly step entirely.
Building a sentence in your first language and converting it is necessarily slow. The first skill is finishing within the expressions you already have. Simplifying what you meant and getting to the end beats stopping halfway to construct a perfect sentence.
Output practice does not require a partner. Narrate what you did today out loud, describe a photograph, or summarise a short video in your own words. Recording yourself reveals the mistakes you repeat, and those are usually few enough that fixing them changes things quickly.
Stopping mid-sentence out of fear of a grammar error reduces the amount of practice itself. Early on the goal is being understood; refining accuracy fits better once speech is flowing. Some errors do harden and become hard to undo, so note the ones you get corrected on repeatedly.
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