1. I bought a ball-point pen at the stationery store.
2. I bought a ballpoint pen at the stationery store.
3. I bought a ball pen at the stationery store.
4. I bought a ballpen at the stationery store.
5. I bought a ball point at the stationery store.
6. I bought a ballpoint at the stationery store.
7. I bought a ball-point at the stationery store.
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Which expressions are correct? Which ones are commonly used? Thank you.
I would not use 3 or 4. The rest are OK, but I believe it's "ballpoint" -- not hyphenated and not two words.
All the expressions you have provided can be considered correct to some extent, but there are a few differences in their usage and preferred spellings. Here's a breakdown:
1. "I bought a ball-point pen at the stationery store." - This expression is correct and commonly used. "Ball-point pen" is a compound noun that refers to a pen with a small rotating ball at its tip, which dispenses ink as you write.
2. "I bought a ballpoint pen at the stationery store." - This expression is correct and widely used. "Ballpoint pen" is an alternative spelling of "ball-point pen," without the hyphen. It is more commonly used in informal writing.
3. "I bought a ball pen at the stationery store." - This expression is correct, but not as commonly used as the previous ones. "Ball pen" is a term used to describe a pen with a small ball at the tip, similar to a ball-point pen.
4. "I bought a ballpen at the stationery store." - This expression is correct, but it is less commonly used. "Ballpen" is a shortened form of "ball-point pen" without a space. While it may not be as common, it is still understandable and can refer to the same type of pen.
5. "I bought a ball point at the stationery store." - This expression is not commonly used and may sound unusual to native English speakers. "Ball point" typically refers to the actual point or tip of a writing instrument, not the pen itself.
6. "I bought a ballpoint at the stationery store." - This expression is correct and commonly used. "Ballpoint" is a noun that describes the type of pen with a small ball at the tip. This spelling is often used in casual or informal writing.
7. "I bought a ball-point at the stationery store." - This expression is correct, although not as commonly used as the other variations. It combines the compound noun "ball-point" with the preposition "at" to specify where the purchase was made.
Overall, expressions 1, 2, 3, 4, 6, and 7 are commonly used, with variations in spelling and hyphen usage. Expressions 5 is less common and may not be understood as easily.