6%
Select the correct option.
How often _________________________ your friends visit you?

The correct answer is "do". In this question, we are asking about the frequency of an action in the simple present tense, so we use "do" as the auxiliary verb.

To ChallengesNext

Predicate

Subject vs predicate: every clause splits into two halves. Subject = who/what the sentence is about. Predicate = what's said about the subject (verb + objects + modifiers). The cat (subject) sat on the mat (predicate). Can't have one without the other in a complete sentence.

The predicate is the verb + everything attached to it. It contains the verb, objects, complements, and modifiers.

Diagnostic: find the main verb. The subject is to its left; the predicate starts at the verb and includes everything to its right. No verb = no predicate = fragment.

Auxiliary verb

Auxiliary vs main verb: a main verb carries the action (run, eat, think); an auxiliary verb carries the grammar — tense, negation, questions, aspect, voice. In She has been eating, eating is the main verb; has and been are auxiliaries.

The English auxiliaries are be, have, do (primary) and the modal verbs (can, will, must…). They always precede the main verb.

Diagnostic: can the word stand alone as the only verb in the sentence and still carry action? Yes → main verb. No → auxiliary.

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.

Questions

Direct vs indirect questions: direct questions invert and end with ? (Where does she live?). Indirect questions DON'T invert and end with a period (I wonder where she lives.). Mixing these up — I wonder where does she live? ❌ — is one of the most common structural errors.

Questions in English use inversion/do-support. Types: yes/no, wh-, negative, tag. Direct questions invert; indirect don't.

Diagnostic: is your question embedded inside a statement (I wonder, Do you know, Can you tell me)? → DON'T invert. Is it a standalone question? → invert.

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, A1A2. Medium = one rule but realistic distractors, A2B1. 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.