The original sentence requires the past simple tense for the first blank and the present perfect tense for the second blank. The verb "to eat" is an irregular verb. Its simple past form is "ate," and its past participle form is "eaten." So, the correct answer is "They ate dinner last night, but they have eaten breakfast yet today."
Simple tense
- ✅ I go to work every day. — present simple (habit)
- ✅ She went home yesterday. — past simple (completed action)
- ✅ I will call you later. — future simple (promise/decision)
- ✅ Water boils at 100°C. — present simple (general truth)
The simple aspect is the default, unmarked verb form. Present simple = habits, facts, schedules. Past simple = completed actions. Future simple = predictions, promises, decisions. No auxiliary needed (except will for future and do for questions/negatives).
Rule: if the action is a fact, habit, completed event, or scheduled future — and you don't need to emphasise it being in-progress or connected to now → simple tense.
Past tense
- I walked home. — simple past (completed action)
- I was walking when it rained. — past progressive (in progress)
- I had already left when she arrived. — past perfect (earlier past)
- I had been waiting for an hour. — past perfect progressive (duration up to a past point)
Four past tense forms: simple past (done), past progressive (was happening), past perfect (had already happened), past perfect progressive (had been happening). Each encodes different timing relative to other past events.
Pattern: simple past = the story's main timeline. Past progressive = background action. Past perfect = flashback to something even earlier.
Verb
- walk → walk / walks / walked / walked / walking (5 forms, regular)
- go → go / goes / went / gone / going (5 forms, irregular)
- be → am/is/are/was/were/be/being/been (8 forms)
- can → can / could (modal: only 2 forms, no -s, no -ing)
A verb is the one word class every English sentence requires. Carries tense (when), aspect (duration), mood (attitude), and voice (active/passive). Regular verbs add -ed; ~200 irregular verbs have unpredictable past forms.
Key insight: fix your verbs and most grammar problems disappear. Wrong tense, wrong agreement, wrong form — verb errors account for the majority of grammatical mistakes.
Irregular verb
- ✅ go → went → gone — ❌ goed / goed
- ✅ eat → ate → eaten — ❌ eated / eated
- ✅ put → put → put — all three forms identical
- ✅ cut → cut → cut — no change group
Irregular verbs don't add -ed for past tense — they change form unpredictably. About 200 common English verbs are irregular, and they include the most frequently used verbs (be, have, go, do, say, make, take).
Pattern: no rule covers all of them. Some rhyme (sing/sang/sung, ring/rang/rung), some don't change (put/put/put), some are unique (go/went/gone). Memorisation is the only path.
Participle
- ✅ a broken window — past participle as adjective
- ✅ the running water — present participle as adjective
- ✅ I have eaten. — past participle in perfect tense
- ✅ She is sleeping. — present participle in progressive tense
- ❌ I have went. — wrong (past tense, not past participle: use gone)
A participle is a verb form that also works as an adjective. Present (-ing): running, sleeping. Past (-ed or irregular): broken, written, gone. Used in progressive tenses, perfect tenses, passive voice, and as modifiers.
Trap: don't confuse past tense (went) with past participle (gone). After have/has/had → always past participle.
Perfect tense
- ✅ I have lived here for ten years. — present perfect (started past, still true)
- ❌ I live here for ten years. — wrong (simple present can't bridge past→now)
- ✅ She had finished before I arrived. — past perfect (earlier past)
- ✅ They will have left by noon. — future perfect (completed before future point)
The perfect = have + past participle. Connects an action to a reference point in time. Present perfect bridges past→now. Past perfect marks "earlier past." Future perfect marks "done before a future deadline."
Rule: if the action started in the past and is still relevant now → present perfect (have done). If two past events and you need the earlier one → past perfect (had done).
B1 | Intermediate
- ✅ If I had more time, I would travel more. — second conditional
- ✅ The bridge was built in 1920. — passive voice
- ✅ She said she was tired. — reported speech with backshift
- ✅ Although it rained, we enjoyed the trip. — complex sentence with concession
These are B1 patterns — the CEFR intermediate level. At B1 you link ideas, use passive voice, handle reported speech, and manage second conditional — enough for travel, work basics, and everyday independence.
Marker: if you can explain why something happened and follow a news story, you're B1.
Easy
- She is a teacher. — one verb form, one rule
- I have two cats. — basic possession, short sentence
- He doesn't like coffee. — simple negation with do-support
- Only one answer is clearly correct; distractors are obviously wrong.
Easy marks beginner-level challenges: A1–early A2, one rule at a time, everyday vocabulary, no trick questions.
Use "Easy" when you want to build confidence on a specific rule without interference from other grammar or tricky contexts.