It is not polite to use imperative sentences without the word "Please". It is better to say "Please, come here." than just "Come here." The simplest English sentences are imperative sentences with a single verb (Example: "Help!").
Sentences may be simple or compound. Compound sentences consist of two or more simple sentences joined by conjunctions.
Examples:
<English Sentence> =
<Simple Sentence> |
<Compound Sentence>
<Simple Sentence> =
<Declarative Sentence> |
<Interrogative Sentence> |
<Imperative Sentence> |
<Conditional Sentence>
<Compound Sentence> =
<Simple Sentence> <conjunction> <Simple Sentence> |
"Either" <Declarative Sentence> "or" <Declarative Sentence> |
"Either" <Imperative Sentence> "or" <Imperative Sentence>