The conjuctions are: "and," "but," "or," "nor," "for," "so," or "yet."
or
and, nor, or, for
conjuctions
And, or, but. Those are the most common.
compound subject
correlative conjuctions
compound subject
A sentence must contain a subject and a verb; it can also have and object and phrases, prepositions, conjuctions, etc
There are seven coordinating conjunctions in the English language: for, and, nor, but, or, yet, so.
The other name that we can use for conjunctions is CONNECTORS, ..they connect nouns, adjectives, sentences...etc.
Yes, it is correct to put a comma before the word "once" when it is used at the beginning of a sentence to indicate a specific time or condition. For example: "Once, I was afraid of heights but now I enjoy rock climbing."
If you mean a sentence like: Alex and Becky went to the store. Then this is a simple sentence.