The correct answers are Humans look at their phones during dinner. and Humans look at their phones while they walk.
During is followed by a noun event (like "dinner").
While is followed by a clause with a subject and a verb (like "they walk"). Earthlings use these words differently, and now you know how!
Preposition
- ✅ interested in — ❌ interested on
- ✅ good at football — ❌ good in football
- ✅ depend on — ❌ depend of
- ✅ arrive at the station — ❌ arrive to the station
Prepositions link nouns to the rest of the sentence: time (at 5pm), place (in London), manner (with care), abstract (afraid of). Most are idiomatic — the "correct" preposition must be memorised with each verb/adjective combination.
Rule: there is no universal rule. English prepositions are learned by combination: interested IN, good AT, depend ON, afraid OF. Your native language's equivalent will often mislead.
Conjunction
- ✅ I was tired, but I stayed. — coordinating (links two equal clauses)
- ✅ I stayed because I was needed. — subordinating (introduces dependent clause)
- ✅ Although it rained, we went out. — subordinating (front position)
- ❌ I was tired, because. — incomplete (subordinating conjunction needs a clause after it)
Conjunctions connect words, phrases, or clauses. Coordinating (and, but, or, so, yet, for, nor) join equals; subordinating (because, although, if, when, while) introduce dependent clauses.
Pattern: coordinating = equal partners, same grammatical weight. Subordinating = one clause depends on the other for its meaning.
Clause
- I missed the bus. — ✅ independent clause (stands alone)
- Because I overslept. — ❌ fragment (dependent clause, can't stand alone)
- Because I overslept, I missed the bus. — ✅ dependent + independent = complete sentence
- I missed the bus, and I was late. — ✅ two independent clauses joined by and
A clause is a unit built around a verb with a subject. Independent = can stand alone. Dependent = needs an independent clause to complete it.
Test: does the group of words have a subject + verb AND can it be a sentence on its own? Yes → independent clause. Has a subject + verb but feels incomplete → dependent clause.
Phrase
- the red car — noun phrase (functions as one noun unit)
- on the table — prepositional phrase
- has been running — verb phrase
- very quickly — adverb phrase
A phrase is a group of words that functions as a single unit WITHOUT a subject + verb pair. Types: noun phrase, verb phrase, prepositional phrase, adjective phrase, adverb phrase.
Key distinction: a phrase lacks a subject-verb pair. If it has subject + verb → it's a clause, not a phrase. Phrases are the building blocks clauses are made of.
A1 | Elementary | Beginners
- ✅ My name is Anna. — present simple of be
- ✅ Where is the station? — basic *wh-*question
- ✅ I have two brothers. — possession with have
- ✅ She likes coffee. — third-person -s
These are A1 sentences — the starting level of the CEFR framework. At A1 you can introduce yourself, ask and answer simple personal questions, and handle basic everyday transactions using present tense, be/have/do, and core vocabulary.
If you can say these but freeze at normal speaking speed, you're solidly A1 — and that's exactly where to start.
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.