1. What is "chem lab"? A chemistry course?
2. What is "store credit"? It's from "I'd like to get my money back, or at least store credit".
3. Here is a sentence---"They give the example of movie stars who used to make these grand entrances."
So what does "grand entrances" refer to?
Hi fraserpan,

The grand entrance that you are talking about goes back a long way before movie stars were around.

It was originally connected with Aristocracy and these large Banquets and Balls that the Queen, King or some other wealthy person would invite people to.

Custom was that each person or couple would enter into the main hall. There the person/s would be announced to all people already inside. The impression made on the attendees by the person, was usually dependent on the title (Duke, Earl, Lord etc), style of clothing or who was by their side etc. This was known as the grand entrance. Through the years, this protocol has evolved, and now it is usually associated with the movies stars and others as they arrive to the premier showing of...The Jackass Movie...for example (just kidding)

Hope this helps.

i am not sure what (1) and (2) mean. i feel "chem lab" is a shortened version of either a chemical lab or a chemistry lab.
in (3), 'grand entrances' refers to the dramatic way the movie stars are introduced in a movie, for example, in the first few minutes of a movie, the hero is shown in a bike-chase scene where he successfully resuces a kid or the heroine from the clutches of a rowdy by performing a super human stunt.
the best example to explain the 'grand entrance' is the way Halle Berry is introduced in the latest James Bond film(oops!! i forgot the name of the fim) where she is shown coming towards Pierce Brosnan in the beach.Emotion: wink
hope that helps.
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"Chem lab" is, I assume, a chemistry lab, but it's not a phrase in common usage. Maybe only chemistry students, or chemists themselves, would use that shortened name for it?

"Store credit" is where you take something back to the shop, but instead of giving you a refund (money back) they allow you to purchase other goods to the same value, inside the shop. Typically, in England, this would happen when the goods weren't faulty, but you just changed your mind. The store is not obliged to refund the money, but they might agree to take the item back, and let you choose something different. If you don't want to buy anything there and then, they may issue a "credit note" for the amount, which you can use next time you visit the store.
Many thanks! Emotion: smile

By the way, the grand entrance is not those movie stars' show-ups that they walk on a red carpet in front of public before entering a theater, especially at a movie festival, is it?
 Timbo's reply was promoted to an answer.
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