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Complete the alien commander's report on Earth's internet.

"The internet has a strange ___ on humans; ___ constantly distracting them from building spaceships."

The correct answer is effect / it's.

You need the noun effect because you are talking about the result of the internet (a strange effect).

You need the contraction it's because the sentence requires "it is" to make sense (it is constantly distracting them).

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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.

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.

Pronoun

Pronouns are a relatively small, closed class of words that function in the place of nouns or noun phrases. They include personal pronouns, demonstrative pronouns, relative pronouns, interrogative pronouns, and some others, mainly indefinite pronouns.

Personal

The personal pronouns of modern standard English, and the corresponding possessive forms, are as follows:

NominativeObliqueReflexivePossessive determinerPossessive pronoun
1st pers. sing.Imemyselfmymine
2nd pers. sing./pl.youyouyourself/yourselvesyouryours
3rd pers. sing.she, he, they, ither, him, them, itherself, himself, themself, itselfher, his, their, itshers, his, theirs, its
1st pers. pl.weusourselvesourours
3rd pers. pl.theythemthemselvestheirtheirs

The second-person forms such as you are used with both singular and plural reference. You can also be used as an indefinite pronoun, referring to a person in general compared to the more formal alternative, one) (reflexive oneself, possessive one's).

The third-person singular forms are differentiated according to the sex of the referent. For example, she is used to refer to a female person, sometimes a female animal, and sometimes an object to which female characteristics are attributed, such as a ship or a country. A male person, and sometimes a male animal, is referred to using he. In other cases it can be used. The word it can also be used as a dummy subject, in sentences like It is going to be sunny this afternoon.

The third-person plural forms such as they are sometimes used with singular reference, as a gender-neutral pronoun, as in each employee should ensure they tidy their desk. Despite its long history, this usage is sometimes considered ungrammatical.

The possessive determiners such as my are used as determiners together with nouns, as in my old man, some of his friends. The second possessive forms like mine are used when they do not qualify a noun: as pronouns, as in mine is bigger than yours, and as predicates, as in this one is mine. Note also the construction a friend of mine (meaning "someone who is my friend").

Demonstrative and Interrogative

The demonstrative pronouns of English are this (plural these), and that (plural those), as in these are good, I like that. Note that all four words can also be used as determiners (followed by a noun), as in those cars. They can also form the alternative pronominal expressions this/that one, these/those ones.

The interrogative pronouns are who, what, and which (all of them can take the suffix -ever for emphasis). The pronoun who refers to a person or people; it has an oblique form whom (though in informal contexts this is usually replaced by who), and a possessive form (pronoun or determiner) whose. The pronoun what refers to things or abstracts. The word which is used to ask about alternatives from what is seen as a closed set: which (of the books) do you like best? (It can also be an interrogative determiner: which book?; this can form the alternative pronominal expressions which one and which ones.) Which, who, and what can be either singular or plural, although who and what often take a singular verb regardless of any supposed number.

All the interrogative pronouns can also be used as relative pronouns; see below for more details.

Relative

The main relative pronouns in English are who (with its derived forms whom and whose), which, and that.

The relative pronoun which refers to things rather than persons, as in the shirt, which used to be red, is faded. For persons, who is used (the man who saw me was tall). The oblique case form of who is whom, as in the man whom I saw was tall, although in informal registers who is commonly used in place of whom.

The possessive form of who is whose (the man whose car is missing ...); however the use of whose is not restricted to persons (one can say an idea whose time has come).

The word that as a relative pronoun is normally found only in restrictive relative clauses (unlike which and who, which can be used in both restrictive and unrestrictive clauses). It can refer to either persons or things, and cannot follow a preposition. For example, one can say the song that [or which] I listened to yesterday, but the song to which [not to that] I listened yesterday. The relative pronoun that is usually pronounced with a reduced vowel, and hence differently from the demonstrative that. If that is not the subject of the relative clause, it can be omitted (the song I listened to yesterday).

The word what can be used to form a free relative clause – one that has no antecedent and that serves as a complete noun phrase in itself, as in I like what he likes. The words whatever and whichever can be used similarly, in the role of either pronouns (whatever he likes) or determiners (whatever book he likes). When referring to persons, who(ever) (and whom(ever)) can be used in a similar way (but not as determiners).

"There"

The word there is used as a pronoun in some sentences, playing the role of a dummy subject, normally of an intransitive verb. The "logical subject" of the verb then appears as a complement after the verb.

This use of there occurs most commonly with forms of the verb be in existential clauses, to refer to the presence or existence of something. For example: There is a heaven; There are two cups on the table; There have been a lot of problems lately. It can also be used with other verbs: There exist two major variants; There occurred a very strange incident.

The dummy subject takes the number (singular or plural) of the logical subject (complement), hence it takes a plural verb if the complement is plural. In informal English, however, the contraction there's is often used for both singular and plural.

The dummy subject can undergo inversion, Is there a test today? and Never has there been a man such as this. It can also appear without a corresponding logical subject, in short sentences and question tags: ''There wasn't a discussion, was there? There was.''

The word there in such sentences has sometimes been analyzed as an adverb, or as a dummy predicate, rather than as a pronoun. However, its identification as a pronoun is most consistent with its behavior in inverted sentences and question tags as described above.

Because the word there can also be a deictic adverb (meaning "at/to that place"), a sentence like There is a river could have either of two meanings: "a river exists" (with there as a pronoun), and "a river is in that place" (with there as an adverb).

Other

Other pronouns in English are often identical in form to determiners (especially quantifiers), such as many, a little, etc. Sometimes, the pronoun form is different, as with none (corresponding to the determiner no), nothing, everyone, somebody, etc. Many examples are listed as indefinite pronouns. Another indefinite (or impersonal) pronoun is one) (with its reflexive form oneself and possessive one's), which is a more formal alternative to generic you.

Apostrophe

The apostrophe (' or ’) character is a punctuation mark, and sometimes a diacritical mark, in languages that use the Latin alphabet and some other alphabets.

In English it is used for several purposes:

  • The marking of the omission of one or more letters (as in the contraction) of do not to don't.
  • The marking of possessive case of nouns (as in the eagle's feathers, or in one month's time).
  • The marking of plurals of individual characters (e.g. p's and q's).

The apostrophe looks the same as a closing single quotation mark in many fonts, although they have different meanings, and Unicode recommends using the quotation mark character to represent most uses of the apostrophe.

Possessives

In English, possessive words or phrases exist for nouns and most pronouns, as well as some noun phrases. These can play the roles of determiners (also called possessive adjectives when corresponding to a pronoun) or of nouns.

For historical reasons, this case is misleadingly called the possessive (case). It was called the genitive until the 18th century and in fact expresses much more than possession. Most disagreements about the use of possessive forms of nouns and of the apostrophe are due to the erroneous belief that a term should not use an apostrophe if it does not express possession.

In the words of the Merriam-Webster Dictionary of English Usage:

The argument is a case of fooling oneself with one's own terminology. After the 18th-century grammarians began to refer to the genitive case as the possessive case, grammarians and other commentators got it into their heads that the only use of the case was to show possession. ...

This dictionary also cites a study in whose samples only 40% of the possessive forms were used to indicate actual possession.

Nouns, noun phrases, and some pronouns generally form a possessive with the suffix -'s (apostrophe plus s, but in some cases just by adding an apostrophe to an existing s). Personal pronouns, however, have irregular possessives, and most of them have different forms for possessive determiners and possessive pronouns, such as my and mine or your and yours.

Possessives are one of the means by which genitive constructions are formed in modern English, the other principal one being the use of the preposition of.

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.