Premium economy shell seats on Japan Airlines. Premium economy is a travel class offered on some airlines. Positioning in price, comfort, and amenities, this travel class is leveled between economy class and business class. In 1991, EVA Air was the first to introduce Evergreen Class and had since become the first airline to offer this class of service in the world.
This sentence has two independent clauses. They are connected by and with a comma before it. The and and the comma are correct. However, adding a comma after thus is not correct because it is an adverb; the comma after it is not necessary. If thus is used as a conjunctive adverb (without and), a semi-colon and a comma are necessary.
(3) Use a comma after an interjection. An interjection is usually a short word inserted into a sentence to express an emotion or feeling. Read more about using a comma after an interjection. (4) Use a comma before a conjunction that joins two independent clauses. Words like and, or, and but are known as conjunctions. Read more about using a comma before a conjunction. Read about the Oxford Comma. (5) Use commas as parentheses to offset a parenthesis. Parentheses are punctuation marks (either commas, dashes or brackets) used in pairs to offset additional information in a sentence (known as a parenthesis).