Principal parts of the sentence. Their general characteristics

The subject and the predicate constitute the backbone of the sentence: without them the sentence would not exist at all, whereas all other parts may or may not be there, and if they are there, they serve to define or modify either the subject or the predicate, or each other.

The subject is one of the 2 main parts of the sentence:

1. It denotes the thing whose action or characteristic is expressed by the predicate.

2. It is not dependent on any other part of the sentence.

It may be expressed by different parts of speech, the most frequent ones being: a noun in the common case, a personal pronoun in the nominative case, a demonstrative pronoun occasionally, a substantivized adjective, a numeral, an infinitive, and a gerund. It may also be expressed by a phrase.

The predicate is one of the 2 main parts of the sentence:

1. It denotes the action or property of the thing expressed by the subject

2. It is not dependent on any other part of the sentence.

3. Ways of expressing the predicate are varied and their structure will better be considered under the heading of types of predicate.

It is sometimes claimed that the predicate agrees in number with the subject: when the subject is in the singular, the predicate is bound to be in the singular, and vice versa. However this statement is very doubtful.

•E.g. My family are early risers. + The question of concord refers to the level of phrases, not sentences.