Gerund

The gerund takes the same form (ending in -ing) as the present participle, but is used as a noun (or rather the verb phrase introduced by the gerund is used as a noun phrase). Many uses of gerunds are thus similar to noun uses of the infinitive. Uses of gerunds and gerund phrases are illustrated below:

As subject or predicative expression:

• Solving problems is satisfying.
• My favorite activity is spotting butterflies.

As object of certain verbs that admit such constructions:

• I like solving problems.
• We tried restarting the computer.

In a passive-type construction after certain verbs, with a gap (zero) in object or complement position, understood to be filled by the subject of the main clause:

• That floor wants/needs scrubbing.
• It doesn't bear thinking about.

As complement of certain prepositions:

• No one is better at solving problems.
• Before jogging, she stretches.
• After investigating the facts, we made a decision.
• That prevents you from eating too much.

It is considered grammatically correct to express the agent(logical subject) of a gerund using a possessive form (they object to my helping them), although in informal English a simple noun or pronoun is often used instead (they object to me helping them).

Phrase

In everyday speech, a phrase may be any group of words, often carrying a special idiomatic meaning; in this sense it is synonymous with expression. In linguistic analysis, a phrase is a group of words (or possibly a single word) that functions as a constituent in the syntax of a sentence, a single unit within a grammatical hierarchy. A phrase typically appears within a clause, but it is possible also for a phrase to be a clause or to contain a clause within it.

Subject

The subject is the part of a sentence or clause that tells you who or what the sentence is about. It typically comes before the verb and controls the verb's form — meaning the verb must agree with the subject in number and person.

How to identify the subject

The subject is usually a noun, pronoun, or noun phrase that performs the action or is described by the predicate.

• She works at a hospital.
• The old bridge collapsed during the storm.
• Running every morning keeps me healthy.

The verb agrees with the subject: She works (singular) vs. They work (plural). This subject-verb agreement is one of the most reliable ways to find the subject.

Self-check trick: Ask "Who or what + verb?" to locate the subject. "Who works at a hospital?" → She. That's your subject.

Types of subjects

• Simple subject — the core noun or pronoun alone: Dogs bark.
• Complete subject — the simple subject plus all its modifiers: The two large dogs next door bark every night.
• Compound subject — two or more subjects joined by a conjunction: Coffee and tea are available.

Tricky cases

Sometimes the grammatical subject isn't the "doer." In passive sentences, the subject receives the action:

• ❌ Thinking the subject must be the doer: "The window" broke itself?
• ✅ The window was broken by a ball. (The window is the subject, but the ball did the breaking.)

English also uses dummy subjects — words like it or there that fill the subject position without carrying real meaning:

• It is difficult to learn French.
• There are three problems with this plan.

In the first example, the "real" subject (the thing that is difficult) is to learn French, but grammatically it holds the subject slot. These are sometimes called expletive subjects.

Why it matters

Getting the subject right is essential for subject-verb agreement, choosing correct pronoun forms (he vs. him), and building clear sentences. Misidentifying the subject is one of the most common sources of grammar errors, especially with longer or inverted sentences.

Practice identifying subjects and building correct sentences with challenges like Basics. Common Questions. and Basics. Pronouns and Possessives..

Preposition

Prepositions form a closed word class, although there are also certain phrases that serve as prepositions, such as in front of.

A single preposition may have a variety of meanings, often including temporal, spatial and abstract. Many words that are prepositions can also serve as adverbs. Examples of common English prepositions (including phrasal instances) are of, in, on, over, under, to, from, with, in front of, behind, opposite, by, before, after, during, through, in spite of or despite, between, among, etc.

A preposition is usually used with a noun phrase as its complement.

A preposition together with its complement is called a prepositional phrase.

Examples are in England, under the table, after six pleasant weeks, between the land and the sea.

A prepositional phrase can be used as a complement or post-modifier of a noun in a noun phrase, as in the man in the car, the start of the fight; as a complement of a verb or adjective, as in deal with the problem, proud of oneself; or generally as an adverb phrase.

English allows the use of "stranded" prepositions. This can occur in interrogative and relative clauses, where the interrogative or relative pronoun that is the preposition's complement is moved to the start (fronted), leaving the preposition in place. This kind of structure is avoided in some kinds of formal English.

For example:

• What are you talking about? (Possible alternative version: About what are you talking?)
• The song that you were listening to ... (more formal: The song to which you were listening ...)

Notice that in the second example the relative pronoun that could be omitted.

Stranded prepositions can also arise in passive voice constructions and other uses of passive past participial phrases, where the complement in a prepositional phrase can become zero in the same way that a verb's direct object would: it was looked at; I will be operated on; get your teeth seen to.

The same can happen in certain uses of infinitive phrases: he is nice to talk to; this is the page to make copies of.

Collocations

Collocations are combinations of words that are frequently used together in a particular order, forming a natural-sounding expression. These word pairs or groups often sound more natural to native speakers than other possible combinations of the same words. Understanding collocations is important for language learners because they help you sound more fluent and natural when speaking or writing.

B2 | Upper Intermediate

B2, or Upper Intermediate, is the fourth level on the CEFR scale. It marks the point where you move from "getting by" to genuinely comfortable communication — handling complex topics, expressing nuanced opinions, and understanding most of what you read or hear in real-world contexts.

What a B2 user can do

At this level, you're expected to:

• Understand complex texts on both concrete and abstract topics, including technical discussions in your own field.
• Follow extended speech and lectures, even when the structure isn't entirely clear, as long as the topic is reasonably familiar.
• Interact fluently and spontaneously enough that conversations with native speakers flow naturally — without strain on either side.
• Produce clear, detailed text on a wide range of subjects, using connectors and cohesive devices to build well-structured arguments.
• Explain and defend a viewpoint on a topical issue, weighing the advantages and disadvantages of different options.
• Recognize implicit meaning — reading between the lines in demanding, longer texts.

What B2 grammar looks like in practice

B2 is where grammar stops being about isolated rules and starts being about flexibility and precision. You're expected to control structures like:

• Advanced conditionals and mixed conditionals — moving beyond simple if-clauses to express hypothetical and counterfactual meaning.
• Passive voice in varied tenses and contexts, not just present and past simple.
• Reported speech with correct sequence of tenses, including backshifting and reporting verbs.
• Participle clauses and the distinction between participles and gerunds.
• Comparative and superlative structures beyond basic -er/-est, including double comparatives and qualifying expressions.

Errors still happen at B2, but they rarely cause misunderstanding. The goal is controlled, flexible use of language across social, academic, and professional settings.

How B2 fits in the CEFR progression

B2 builds directly on the foundations of B1 (Intermediate) and prepares you for C1 (Advanced). Many university entrance exams, professional certifications, and immigration requirements target B2 as the minimum standard.

Self-check: If you can read a newspaper editorial, follow most of a TED talk without subtitles, and write a clear essay arguing a position — you're likely operating at B2.

Ready to test yourself? Try Is your English level B2/Upper Intermediate? or practise specific B2 grammar with challenges like Basics. Advanced Conditionals And "wish", Basics. Passive Voice, and Sequence of Tenses in Indirect Speech.

Difficulty: Hard

Hard difficulty. Difficulty levels represent author's opinion about how hard a question or challenge is.