Functions of a Sentence
The subject must be a noun or a phrase or clause acting as a noun, and the predicate must include a verb. We have an example here: Fred and his wife liked to cook. The subject here is “Fred and his wife”. We have “Fred” and “wife”, which are both nouns. That’s the topic of the sentence.
The topic of the sentence here is “Fred and his wife”, because they are the ones that are going to be doing the action. Now, the predicate here is “like to cook”. The predicate must include a verb, and the verb here is “like”. The predicate comments on the topic of the sentence.
Here, the topic is “Fred and his wife”, and the predicate is commenting, saying that Fred and his wife like to cook. Now, the purpose of a sentence refers to its function. Does the sentence state a fact or an opinion? Does it ask a question? Does it give a command, or does it show excitement?
The first type of sentence is declarative. It makes a statement and ends with the period. “Animals have their own language.” That’s a declarative sentence. An interrogative sentence asks a question and ends with a question mark.
Like, “Do animals have their own language?” An imperative sentence gives a command or makes a request. It ends with a period or an exclamation point. Like here, we have “Carry that box.” You may be thinking that this sentence does not have a noun in it acting as the subject.
Well, many times in imperative sentences, there is an understood “you” as the subject. W actually could write this sentence as “You carry that box,” but we can leave “you” out and just write “Carry that box,” and we know that the subject is actually “you”.
Then, there are exclamatory sentences, like “How beautiful she is!” An explanatory sentence shows sudden or strong feeling, and it ends with an exclamation point. Again, the four types of sentences are declarative, interrogative, imperative, and exclamatory.