45%

Help the mad scientist finalize his evil laboratory report.

"The new potion will ___ the town's water supply, creating a disastrous ___ on everyone's hair color."

The correct answer is affect / effect.

Affect is almost always a verb meaning "to influence or change" (The potion will affect the water).

Effect is almost always a noun meaning "the result of a change" (creating a disastrous effect).

Helpful trick: Think of the acronym RAVEN: Remember Affect Verb, Effect Noun.

To ChallengesPreviousNext

Verb

A verb is a word that expresses an action, a state, or an occurrence — and it's the engine of every English sentence. Understanding how verbs work is foundational to everything else in English grammar, from forming questions to building complex sentences.

Verb Forms

Most English verbs have five inflected forms:

  • Base form (go, write, climb) — used as an infinitive, imperative, present subjunctive, and present indicative in all persons except third-person singular.
  • -s form (goes, writes, climbs) — used for the present tense, third-person singular (she writes).
  • Past tense (went, wrote, climbed) — also called the preterite.
  • Past participle (gone, written, climbed) — identical to the past tense for regular verbs, but often different for irregular verbs.
  • -ing form (going, writing, climbing) — serves as the present participle and gerund.

The verb be is a special case with more forms than any other English verb (am, is, are, was, were, been, being). Modal verbs like can, must, and should have fewer forms than typical verbs.

Main Verbs and Auxiliaries

Verbs in English often appear in combinations: one or more auxiliary verbs paired with a main verb.

  • The dog was barking very loudly.
  • My hat has been cleaned.
  • Jane does not really like us.

The first verb in the combination is the finite verb (it carries tense and agrees with the subject). The rest are nonfinite (infinitives or participles). Notice that these verbs don't always sit next to each other — as in does not really like.

Tense, Aspect, and Mood

English expresses tense (time reference), aspect (how an action unfolds over time), and mood (the speaker's attitude toward the action) mostly through verb combinations rather than word endings. That's why you'll encounter labels like "present progressive" or "conditional perfect" — these are specific tense–aspect–mood combinations built with auxiliaries.

Self-check: If you can change the time of a sentence by swapping one word (She runs → She ran), that word is the verb.

Keep Practising

To build your verb skills from the ground up, try these challenges: Basics. "To be" in Present Tense, Basics. Common Uses of Auxiliary Verbs, and Transitive and Intransitive Verbs.

Noun

A noun (from Latin nōmen, literally meaning "name") is a word that functions as the name of some specific thing or set of things, such as living creatures, objects, places, actions, qualities, states of existence, or ideas. Linguistically, a noun is a member of a large, open part of speech whose members can occur as the main word in the subject of a clause, the object of a verb, or the object of a preposition.

Lexical categories (parts of speech) are defined in terms of the ways in which their members combine with other kinds of expressions. In English, nouns are those words which can occur with articles and attributive adjectives and can function as the head of a noun phrase.

Simple Future

The term simple future, future simple or future indefinite, as applied to English, generally refers to the combination of the modal auxiliary verb will with the bare infinitive of the main verb.

Sometimes (particularly in more formal or old-fashioned English) shall is preferred to will when the subject is first person (I or we).

The auxiliary is often contracted to _ 'll_.

This construction can be used to indicate what the speaker views as facts about the future, including confident predictions:

  • The sun will rise tomorrow at 6:14.
  • It will rain later this week.

It may be used to describe future circumstances that are subject to some condition:

  • He will go there if he can.

However English also has other ways of referring to future circumstances. For planned or scheduled actions the present progressive or simple present may be used. There is also a going-to future, common in colloquial English, which is often used to express intentions or predictions (I am going to write a book some day; I think that it is going to rain). Use of the will/shall construction when expressing intention often indicates a spontaneous decision:

  • I know! I'll use this book as a door stop.

Compare I'm going to use..., which implies that the intention to do so has existed for some time.

Use of present tense rather than future constructions in condition clauses and certain other dependent clauses is described below under and. The modal verbs will and shall also have other uses besides indicating future time reference. For example:

  • I will pass this exam. (often expresses determination in addition to futurity)
  • You will obey me! (insistence)
  • I will not do it! (negative insistence, refusal)
  • At this moment I will tolerate no dissent. (strong volition)
  • He hasn't eaten all day; he will be hungry now. (confident speculation about the present)
  • One of his faults is that he will make trouble unnecessarily. (habit)
  • Shall we get to work? (suggestion)

Future Progressive

The future progressive or future continuous combines progressive aspect with future time reference; it is formed with the auxiliary will (or shall in the first person, the bare infinitive be, and the present participle of the main verb.

It is used mainly to indicate that an event will be in progress at a particular point in the future:

  • This time tomorrow I will be taking my driving test.
  • I imagine we will already be eating when you arrive.

The usual restrictions apply, on the use both of the future and of the progressive: simple rather than progressive aspect is used with some stative verbs, and present rather than future constructions are used in many dependent clauses. The same construction may occur when will or shall is given one of its other uses, for example:

  • He will be sitting in his study at this time. (confident speculation about the present)

Future Perfect

The future perfect combines aspect with future time reference.

It consists of the auxiliary will (or sometimes shall in the first person, as above), the bare infinitive have, and the past participle of the main verb.

It indicates an action that is to be completed sometime prior to a future time of perspective, or an ongoing action continuing up to a future time of perspective (compare uses of the present perfect above).

  • I shall have finished my essay by Thursday.
  • When I finally search him he will have disposed of the evidence.
  • By next year we will have lived in this house for half a century.

For the use of the present tense rather than future constructions in certain dependent clauses.

The same construction may occur when will or shall is given one of its other meanings; for example:

  • He will have had his tea by now. (confident speculation about the present)
  • You will have completed this task by the time I return, is that understood? (giving instruction)

Future Perfect Progressive

The future perfect progressive or future perfect continuous combines perfect progressive aspect with future time reference.

It is formed by combining the auxiliary will (or sometimes shall, as above), the bare infinitive have, the past participle been, and the present participle of the main verb.

Uses of the future perfect progressive are analogous to those of the present perfect progressive, except that the point of reference is in the future. For example:

  • He will be very tired because he will have been working all morning.
  • By 6 o'clock we will have been drinking for ten hours.

For the use of present tense in place of future constructions in certain dependent clauses.

The same construction may occur when the auxiliary (usually will) has one of its other meanings, particularly expressing a confident assumption about the present:

  • No chance of finding him sober now; he*'ll have been drinking* all day.

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: Medium

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