- Dual subtitles give a full translation, so your eyes jump between two lines.
- Swapped words keep one line and add a few words of the language you learn.
- Dual lines suit B1+ learners checking meaning; swaps suit A1 to B1.
How dual subtitles work
Dual subtitles, in tools like Language Reactor, show two lines: the original and a translation. You can read either one, and hover words for more.
It is useful when you can almost follow the original and want to check the meaning. At lower levels, most people read only the line they understand.
How swapped words work
NativeLingo keeps one line in your language and swaps a few words into the one you learn. The words match your level and stand in the right form.
The line stays readable, because reading research puts comfortable understanding at about 98% known words. The new words get your attention because they are few.
Which one suits you
Using both
They solve different problems, so some learners use both. Swaps go on for everyday watching, dual subtitles for a scene worth studying line by line.
Questions
Reading two lines takes longer, so fast scenes can pass before you finish.
No. It swaps a few words in one line instead.
There is no direct study comparing the two. Captioned video in general helps listening and vocabulary.