Semi-fixed Expressions
Semi-fixed expressions are formulaic sequences containing one or more variable slots within an otherwise stable frame. They are more flexible than Fixed Expressions but more predictable and conventionalised than free combinations of words.
Structure
The defining feature is a fixed frame with open positions:
| Frame | Variable slot | Examples |
|---|---|---|
| the ___er, the ___er | adjective/adverb | the sooner, the better; the bigger, the better |
| not only X but also Y | clause/phrase | not only cheap but also effective |
| it's worth ___ing | verb | it's worth considering/trying/mentioning |
| as far as ___ is concerned | noun phrase | as far as grammar is concerned |
| a/an ___ of ___ | noun + noun | a matter of time; a lack of evidence |
| there's no point (in) ___ing | verb | there's no point arguing |
Position on the Formulaic Continuum
Formulaic Language exists on a continuum from fully fixed to fully free:
Fixed → by the way (no variation) Semi-fixed → it's no use ___ing (frame + slot) Collocation → make a decision (strong tendency, some variation) Free combination → read a long book (unrestricted)
Semi-fixed expressions occupy the productive middle ground: predictable enough to aid fluency, flexible enough to be generative.
Teaching Value
Lewis (1993, 1997) argued in the Lexical Approach that semi-fixed expressions deserve more classroom time than they typically receive. They are:
- Frequent — They recur across genres and registers
- Generative — Learning one frame unlocks multiple instances
- Fluency-building — Retrieving a frame with a slot is faster than constructing from scratch
Activities include gap-fill exercises highlighting the frame, matching frames to completions, and noticing tasks using Concordance Lines from corpora to see how frames are filled in authentic language.
Distinction from Collocations
Collocations are about the statistical tendency of words to co-occur (heavy rain, make a mistake). Semi-fixed expressions are about structural frames with predictable patterns. A collocation is a word-level phenomenon; a semi-fixed expression is a clause- or phrase-level phenomenon.