Subject - Verb Agreement

l though you are probably already familiar with basic subject-verb agreement, this chapter begins with a quick review of basic agreement rules.

Subjects and verbs must AGREE with one another in number (singular or plural).  Thus, if a subject is singular, its verb must also be singular; if a subject is plural, its verb must also be plural.

In the present tense, nouns and verbs form plurals in opposite ways: nouns ADD an s to the singular form; verbs REMOVE the s from the singular form.

ACTIVE / PASSIVE VOICE

Active voice
In most English sentences with an action verb, the subject performs the action denoted by the verb.
    These examples show that the subject is  doing the verb's action.
           
Because the subject does or "acts upon" the verb in such sentences, the sentences are said to be in the active voice.

Passive voice
One can change the normal word order of many active sentences (those with a direct object) so that the subject is no longer active, but is, instead, being acted upon by the verb - or passive.
    Note in these examples how the subject-verb relationship has changed.
           
Because the subject is being "acted upon" (or is passive), such sentences are said to be in the passive voice

Tense

A tense is a grammatical category that locates a situation in time, to indicate when the situation takes place. Some typical tenses are present, past, and future.

Tense can make finer distinctions than simple past-present-future; past tenses for example can cover general past, immediate past, or distant past, with the only difference between them being the distance on the timeline between the temporal reference points. Such distinctions are not precise: an event may be described in the remote past because it feels remote to the speaker, not because a set number of days have passed since it happened; it may also be remote because it is being contrasted with another, more recent, past event. This is similar to other forms of deixis such as this and that.

In absolute tense, as in English, tense indicates when the time of assertion, time of completion, or time of evaluation occurs relative to the utterance itself (time of utterance). In relative tense, on the other hand, tense is relative to some given event.

The number of tenses in a language may be disputed, because the term tense is often used to represent any combination of tense proper, aspect, and mood. In many texts the term "tense" may erroneously indicate qualities of uncertainty, frequency, completion, duration, possibility, or whether information derives from experience or hearsay (evidentiality). Tense differs from aspect, which encodes how a situation or action occurs in time rather than when. In many languages, there are grammatical forms which express several of these meanings (see tense–aspect–mood).

In languages which have tenses, they are normally usually indicated by a verb or modal verb. Some languages only have grammatical expression of time through aspect; others have neither tense nor aspect. Some East Asian isolating languages such as Chinese express time with temporal adverbs, but these are not required, and the verbs are not inflected for tense. In Slavic languages such as Russian a verb may be inflected for both tense and aspect together.

Verbs

Regular and irregular 

To make the past tense or past participle form of most verbs (regular verbs) we simply add “ed” at the end.

Examples using the verb “walk”:
Past Tense: I walked through the maze.
Past Participle: I have walked through the maze.
(The past participle form is used in the present perfect, past perfect, and future perfect tenses. The above example is written in the present perfect tense.)
Irregular verbs are not that simple. We sometimes need a dictionary to help us write the different forms of irregular verbs.
Examples using the verb “see”:
Past Tense: We saw the secret maps.
Past Participle: We have seen the secret maps.
Look up the word “see” in the dictionary. Notice that the different forms of the word are given. Look up “walk.” Notice that the dictionary doesn’t bother to give the different forms of regular verbs.

Nouns

A common noun is a general name for a class of objects ,people or places
A proper noun is name of a specific person,place or thing, A proper noun always begins with a capital letter 

Direct and indirect object

The direct object tells us who or what receives the action of the verb

An indirect object tells us to whom or for whom an action is done .

Subject and predicate

Every complete sentence contains two parts: a subject and apredicate. The subject is what (or whom) the sentence is about, while the predicate tells something about the subject. In the following sentences, the predicate is enclosed in braces ({}), while the subject is highlighted.