The correct answer is "happening". In this question, we are asking about an ongoing situation, so we use "happening."
Subject
The subject is the part of a sentence or clause that tells you who or what the sentence is about. It's typically a noun, pronoun, or noun phrase that comes before the verb and controls the verb's form: She works (singular) vs They work (plural).
The subject isn't always the doer of the action — in passive sentences, it receives the action (The window was broken). English also uses dummy subjects like it and there that hold the subject slot without carrying real meaning (It is raining; There are problems). Spotting the real subject is what makes subject-verb agreement automatic.
Questions
Questions in English are typically formed by inverting the subject and an auxiliary verb: She can dance → Can she dance?. When there's no auxiliary present, English adds do-support: The milk goes in the fridge → Does the milk go in the fridge?. The same pattern handles wh-questions (Where do you live?) and negative questions (Doesn't he know?).
The trickiest variant is indirect questions — I wonder where he is, not where is he. The inversion drops because the question is embedded inside another clause. Getting this right is one of the bigger jumps from A2 to B1 fluency.
A2 | Elementary | Pre-intermediate
A2 is the elementary level in the CEFR framework, sitting between A1 and B1. At A2 you can handle routine exchanges — ordering food, asking directions, making small talk — and describe your immediate environment in simple sentences.
Grammatically, A2 introduces past simple and past continuous, present perfect for experiences, basic modal verbs, and the first conditional. You're also picking up collocations and learning which verbs take gerunds vs. infinitives. Knowing your level here is the difference between confident progress and frustration: A2 material consolidates the basics; B1 will overwhelm you.
Difficulty: Easy
The Easy difficulty tag marks questions and challenges aimed at beginners — typically A1 or early A2 level. Expect single-rule focus, short sentences, common everyday vocabulary, and one clear correct answer. Distractors usually rule themselves out quickly.
Filter by Easy when you're rebuilding fundamentals, warming up before harder material, or testing whether you've truly internalised a basic rule before moving on. Easy doesn't mean trivial — it means the rule itself is unambiguous and the context doesn't pile on extra complications.