Help the student complete their rather unusual excuse to the professor by choosing the correct verb.
"I swear, Professor! My cat _____ on my keyboard all night and deleted my entire essay!"
The correct answer is walked.
To talk about a completed action in the past, we use the Past Simple tense. For regular verbs like "walk," we simply add "-ed" to the end of the base verb to make "walked."
Simple tense
Simple vs progressive vs perfect: simple = "just the fact" (I work). Progressive = "ongoing right now" (I am working). Perfect = "connected to a reference time" (I have worked). Simple is the default — use it unless you have a reason to add progressive or perfect meaning.
The simple aspect = unmarked form. Habits, facts, completed events, scheduled future. The starting point for all tense learning.
Diagnostic: do you need to signal "ongoing" (progressive) or "relevant to now" (perfect)? No? → simple is correct. Most sentences use simple tense — it's the unmarked default.
Past tense
Simple past vs past perfect: simple past puts events on the main timeline (I arrived. She left.). Past perfect marks an event as earlier than another past event (She had left before I arrived). If all events are in sequence, simple past is enough. Only use past perfect when you need to show "earlier than the main story."
The past tense has four forms encoding different temporal relationships: simple past, past progressive, past perfect, past perfect progressive.
Diagnostic: are events in sequence? → simple past is fine. Need to show one event happened before another past event? → past perfect for the earlier one.
Verb
Verb vs noun vs adjective: nouns name things. Adjectives describe. Verbs express what happens or what IS. The test: can it take tense (walked, will walk)? Can it take -ing? Can it follow to as an infinitive (to walk)? Yes to any → verb. English often converts freely between classes (run = noun or verb), so context decides.
A verb = action/state/occurrence word. 5 forms (base, -s, past, past participle, -ing). Carries tense, aspect, mood, voice. The one required element in every sentence.
Diagnostic: does it change for tense (walk → walked)? Can you put to before it (to walk)? Does it take -ing (walking)? → verb.
Humor
Humor vs serious practice: both teach the same rules. The difference is engagement — funny material keeps you coming back and creates stronger memory hooks. If dry drills bore you into quitting, humorous practice is more effective because you actually do it.
The Humor tag filters for entertaining practice: silly contexts, wordplay, absurd examples — all testing real grammar rules underneath.
Diagnostic: if you find yourself dreading practice → try filtering by Humor. If you're preparing for a formal exam and want serious register → filter it out.
A1 | Elementary | Beginners
A1 vs A2: A1 covers isolated survival phrases (Where is…?, I am…, How much?). A2 handles connected sentences about familiar routines and simple past events. If you can manage short fixed phrases but not string together original sentences about your day, you're still A1.
A1 is the entry level of the CEFR: greetings, introductions, numbers, basic present tense, and core function words.
Diagnostic: can you describe yesterday using past tense? No → A1. Yes → you're moving into A2.
Easy
Easy vs Medium vs Hard: Easy = one rule, obvious answer, A1–A2. Medium = one rule but realistic distractors, A2–B1. Hard = interacting rules, edge cases, B2+. Start Easy to check you have the basics before moving up.
The Easy tag filters for single-rule, short-sentence, common-vocabulary challenges designed for beginners or for anyone wanting a confidence check on fundamentals.
Diagnostic: if you get Easy questions wrong, stay here — your foundations need work. If they feel trivial, move to Medium.