eng8-u2-mistake-detector· UNIT 2. FOOD AROUND THE WORLD· ~15 min

Unit 2 Mistake Detector: Explain your corrections

Diagnose vocabulary and tense errors, then choose a precise correction.

A good mistake detector does more than replace a word: it names the clue and the rule. A duration takes for, while since introduces a starting point or starting event. After a quantity expression such as levels of, use the noun fat rather than the adjective fatty. Finished times such as last weekend, last year, last night, and yesterday call for Past Simple in these contrasts. A general life-experience statement can use Present Perfect, then a dated example switches to Past Simple. In a negative Present Perfect sentence, yet expresses an expected event that has not happened so far.

Key terms

error clue — a word or context detail that shows why a form is unsuitable
duration — a length of time, introduced by for in the target pattern
starting event — the event after since that marks when a continuing state began
finished time — a past time that is over, such as last year or yesterday
Repair map
ClueProblemRepair
five yearssince + durationfor five years
levels ofadjective fattynoun fat
last weekend / last nightPresent PerfectPast Simple
since + eventPresent Perfect in boundary clausesince + Past Simple
negative expected eventalreadyyet
yesterday negativehave not + participledid not + base verb
✎Explain a correction
  1. 1Find the clue: The sentence contains yesterday, a finished time.
  2. 2Name the error: Haven’t had is Present Perfect and conflicts with that finished-time contrast.
  3. 3Repair the form: Use didn’t have: I didn’t have lunch yesterday.
💡Correct the cause

State why the original form fails before choosing a replacement.

🚫Do not scan one word only

A form can be correct elsewhere; judge it with the sentence’s meaning and time frame.

Rules

  1. 1Use for + duration: for five years.
  2. 2Use Past Simple for the completed starting event in this pattern: since he finished school.
  3. 3Use a noun after levels of: levels of fat, salt, and sugar.
  4. 4Use never when context means no experience at any time up to now.
  5. 5Use Past Simple for actions and states tied to a finished past time.
  6. 6Use did not + base verb for a negative completed past event.
  7. 7Use yet at the end of a negative Present Perfect statement about an expected event.
  8. 8Keep Present Perfect for general experience, then switch to Past Simple for a dated example.

Practice

3 easy · 3 medium · 3 hard

Up to 10 random questions per test

EasyMediumHardMixed