Sentence completion questions give you the beginning of a sentence and ask you to complete it using words from the reading passage. They're faster than matching headings, but the word limit and grammar constraints catch many students off-guard.
Two Rules That Cost Students Marks
Rule 1 — Word limit is absolute. "No more than three words" means your answer can have one, two, or three words — never four. Students who write grammatically perfect four-word phrases lose the mark even if the meaning is correct.
Rule 2 — Grammar must work. Your completed sentence must be grammatically correct. If the stem ends with "in" and your answer starts with "a", double-check it reads naturally: "The experiment was conducted in [a controlled laboratory]" — that works. "The experiment was conducted in [laboratory conditions]" — that also works. Know what class of word fits.
The Process
- Read the sentence stem and identify what type of word is needed (noun? verb? adjective? time expression?)
- Scan the passage for the relevant section — stems usually appear in passage order
- Find the specific phrase in the passage that completes the sentence
- Check the word count — count articles and prepositions
- Check grammar — does the completed sentence read correctly?
Common Mistakes
- Copying more words than allowed — the most common error
- Choosing words from the wrong section of the passage
- Missing the grammar check — your answer must grammatically complete the sentence
Related Guides
→ Summary completion · Multiple choice · Skimming and scanning