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.

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".

Complement

In grammar, a complement is a word, phrase or clause that is necessary to complete the meaning of a given expression. Complements are often also arguments (expressions that help complete the meaning of a predicate.

There are indicative as well as non-indicative complements in languages. Non-indicative complements follow the appropriate complementizers. Indicative complements do not follow complementizers but instead are included with special markers and clauses.

In many non-theoretical grammars, the terms subject complement and object complement are employed to denote the predicative expressions that serve to assign a property to a subject or an object:

• Ryan is upset. – Predicative adjective as subject complement
• Rachelle is the boss. – Predicative nominal as subject complement
• That made Michael lazy. – Predicative adjective as object complement
• We call Rachelle the boss. – Predicative nominal as object complement

The Cambridge Grammar of the English Language assigns the term "predicative complement" to both uses and shifts the terminological distinction to the verb:

• Ed seemed quite competent: — complex-intransitive verb + predicative complement
• She considered Ed quite competent : — complex-transitive verb + predicative complement

In many modern grammars, the object argument of a verbal predicate is called a complement. In fact, this use of the term is the one that currently dominates in linguistics. A main aspect of this understanding of complements is that the subject is usually not a complement of the predicate:

• He *wiped the counter*. – the counter is the object complement of the verb wiped.
• She *scoured the tub*. – the tub is the object complement of the verb scoured.

B1 / Intermediate

A CEFR B1 level English language user is considered to be at an intermediate level. A B1 level English language user is expected to have the following abilities:

• Can understand sentences and frequently used expressions related to areas of most immediate relevance (e.g. very basic personal and family information, shopping, local geography, employment).
• Can communicate in simple and routine tasks requiring a simple and direct exchange of information on familiar and routine matters.
• Can describe in simple terms aspects of their background, immediate environment and matters in areas of immediate need.
• Can understand the main points of clear standard input on familiar matters regularly encountered in work, school, leisure, etc.
• Can produce simple connected text on topics that are familiar or of personal interest.
• Can describe experiences and events, dreams, hopes & ambitions and briefly give reasons and explanations for opinions and plans.

At B1 level, English language users are expected to have a basic level of proficiency in the language. They should be able to understand and produce language in simple and routine tasks, and be able to communicate in familiar and routine matters. They should be able to understand the main points of clear standard input on familiar matters and be able to produce simple connected text on topics that are familiar or of personal interest. They are able to express themselves with a degree of fluency, but with some hesitation, and occasional errors in grammar and vocabulary.

B1 | Intermediate.

Difficulty: Medium

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