Verb

Verbs constitute one of the main word classes in the English language. Like other types of words in the language, English verbs are not heavily inflected. Most combinations of tense, aspect, mood and voice are expressed periphrastically, using constructions with auxiliary verbs.

Generally, the only inflected forms of an English verb are a third person singular present tense form in -s, a past tense, a past participle (which may be the same as the past tense), and a form ending in -ing that serves as a present participle and gerund. Most verbs inflect in a simple regular fashion, although there are about 200 irregular verbs; the irregularity in nearly all cases concerns the past tense and past participle forms. The copula verb be has a larger number of different inflected forms, and is highly irregular.

A typical English verb may have five different inflected forms:

• The base form or plain form (go, write, climb), which has several uses—as an infinitive, imperative, present subjunctive, and present indicative except in the third-person singular
• The -s form (goes, writes, climbs), used as the present indicative in the third-person singular
• the past tense or preterite (went, wrote, climbed)
• The past participle (gone, written, climbed) – this is identical to the past tense in the case of regular verbs and some irregular ones (here the first two verbs are irregular and the third regular)
• The -ing form (going, writing, climbing), used as a present participle, gerund, and (de)verbal nounThe verb be has a larger number of different forms (am, is, are, was, were, etc.), while the modal verbs have a more limited number of forms.

Some forms of be and of certain other auxiliary verbs also have contracted forms ( 's, 're, 've, etc.).

In English, verbs frequently appear in combinations containing one or more auxiliary verbs and a nonfinite form (infinitive or participle) of a main (lexical) verb.

Examples

The first verb in such a combination is the finite verb, the remainder are nonfinite (although constructions in which even the leading verb is nonfinite are also possible – see below). Such combinations are sometimes called compound verbs; more technically they may be called verb catenae, since they are not generally strict grammatical constituents of the clause.

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

As the last example shows, the words making up these combinations do not always remain consecutive.

Tenses, Aspects and Moods

The means English uses for expressing the three categories of tense (time reference), aspect and mood are somewhat conflated. English has only limited means for expressing these categories through verb conjugation, and tends mostly to express them periphrastically, using the verb combinations mentioned in the previous section. The tenses, aspects and moods that may be identified in English are described below (although the terminology used differs significantly between authors). Note that in common usage, particular tense–aspect–mood combinations such as "present progressive" and "conditional perfect" are often referred to simply as "tenses".

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.

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).

Infinitive

Regarding English, the term infinitive is traditionally applied to the unmarked form of the verb when it forms a non-finite verb, whether or not introduced by the particle to.

Hence sit and to sit, as used in the following sentences, would each be considered an infinitive:

• I can sit here all day.
• I want to sit on the other chair.

The form without to is called the bare infinitive; the form introduced by to is called the full infinitive or to-infinitive.

The other non-finite verb forms in English are the gerund or present participle (the -ing form), and the past participle – these are not considered infinitives.

Moreover, the unmarked form of the verb is not considered an infinitive when it is forms a finite verb: like a present indicative ("I sit every day"), subjunctive ("I suggest that he sit"), or imperative ("Sit down!"). (For some irregular verbs the form of the infinitive coincides additionally with that of the past tense and/or past participle, like in the case of put.)

Certain auxiliary verbs are defective in that they do not have infinitives (or any other non-finite forms).

This applies to the modal verbs (can, must, etc.), as well as certain related auxiliaries like the had of had better and the used of used to. (Periphrases can be employed instead in some cases, like (to) be able to for can, and (to) have to for must.) It also applies to the auxiliary do, like used in questions, negatives and emphasis like described under do-support. Infinitives are negated by simply preceding them with not.

Of course the verb do when forming a main verb can appear in the infinitive. However, the auxiliary verbs have (used to form the perfect) and be (used to form the passive voice and continuous aspect) both commonly appear in the infinitive: "I should have finished by now"; "It's thought to have been a burial site"; "Let him be released"; "I hope to be working tomorrow."

Perfect Infinitive

There are nonfinite constructions that are marked for perfect, progressive or perfect progressive aspect, using the infinitives, participles or gerunds of the appropriate auxiliaries. The meanings are as would be expected for the respective aspects: perfect for prior occurrence, progressive for ongoing occurrence at a particular time. (Passive voice can also be marked in nonfinite constructions – with infinitives, gerunds and present participles – in the expected way: (to) be eaten, being eaten, having been eaten, etc.)

Examples of nonfinite constructions marked for the various aspects are given below.

Bare infinitive:

• You should have left earlier. (perfect infinitive; for similar constructions and their meanings see modal verbs)
• She might be revising. (progressive; refers to an ongoing action at this moment)

• He must have been working hard. (perfect progressive; i.e. I assume he has been working hard)

To-infinitive:

• He is said to have resigned. (perfect infinitive)
• I expect to be sitting here this time tomorrow. (progressive)
• He claims to have been working here for ten weeks. (perfect progressive)

Present participle:

• Having written the letter, she went to bed. (perfect)
• The man having left, we began to talk. (perfect, in a nominative absolute construction)
• Having been standing for several hours, they were beginning to feel tired. (perfect progressive)

Past participle:

• We have been waiting a long time. (progressive, used only as part of a perfect progressive construction)

Gerund:

• My having caught the spider impressed the others. (perfect)
• We are not proud of having been drinking all night. (perfect progressive)

Other aspectual, temporal and modal information can be marked on nonfinite verbs using periphrastic constructions. For example, a "future infinitive" can be constructed using forms such as (to) be going to eat or (to) be about to eat.

C2 / Proficiency

A CEFR C2 level English language user is considered to be at Proficiency level. A C2 level English language user is expected to have an even higher level of proficiency than a C1 level user. They are expected to have the following abilities:

• Can understand with ease virtually everything heard or read.
• Can express themselves spontaneously, very fluently and precisely, differentiating finer shades of meaning even in more complex situations.
• Can use the language effectively and appropriately in their professional and academic life.
• Can produce clear, well-structured, detailed text on complex subjects, showing controlled use of organizational patterns, connectors, and cohesive devices.
• Can understand a wide range of demanding, longer texts, and recognize implicit meaning.
• Can express themselves fluently and spontaneously without much obvious searching for expressions.

At C2 level, English language users are expected to have a near-native level of proficiency. They should have a mastery of the language and have a full range of idiomatic expressions, colloquialism and cultural references. They should be able to understand and produce language with ease, even in highly complex situations. They should be able to communicate with native speakers with fluency, spontaneity and precision, showing an excellent command of the language. They should be able to use the language appropriately and effectively in academic and professional settings.

C2 | Proficiency.

C1 / Advanced

A CEFR C1 level English language user is considered to be at Advanced level. A C1 level English language user is expected to have the following abilities:

• Can understand a wide range of demanding, longer texts, and recognize implicit meaning
• Can express themselves fluently and spontaneously, almost effortlessly.
• Can use language flexibly and effectively for social, academic and professional purposes.
• Can produce clear, well-structured, detailed text on complex subjects, showing controlled use of organizational patterns, connectors and cohesive devices.
• Can understand specialized articles and longer technical instructions, even when they do not relate to their field.
• Can use the language effectively and appropriately in their professional and academic life.

At C1 level, English language users are expected to have a high level of fluency and comprehension, with the ability to understand and produce complex language with ease. They should be able to communicate effectively in a variety of settings, both social and professional, using the language flexibly and appropriately. They should also be able to understand specialized texts and technical instructions with little difficulty.

C1 | Advanced.

Difficulty: Hard

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