grammar : what vs. which
“What” is broader than “which”. “Which” … usually means “Which one”. “What” more often means “What kind of”.Here are some examples:
“Which newspapers do you read?” “I read the Houston Chronicle and the Wall Street Journal.” (But not the New York Times, The Guardian, etc.)
“What newspapers do you read?” “Newspapers about business and the stock market.” (= what kind of newspapers)
“Which girl would you like to date?” “The one in the red dress.” (But not one of the other girls in the room.)
“What girl would you like to date?” “One who is intelligent and sweet and pretty.”
How many of these words and phrases might you confuse?
All of the below were excellent confusion candidates for me prior to reading this list…
all together / altogether: All together now — “We will refrain from using that two-word phrase to end sentences like this one altogether.”
forgo / forego: To forgo is to go without; to forego is to go before (and is generally used only in the forms foregoing and foregone, which are themselves rare).
gibe / jibe / jive: To gibe (soft g, as in gym) is to taunt or insult (thoughjibe is an alternate spelling), to jibe with is to coincide or fit, to jive is to deceive.
leach / leech: To leach is to dissolve by percolation; to leech is to remove blood with a leech or to exhaust; as a noun, it means a parasitic worm or the human figurative equivalent, or the edge of a sail (also spelledleach).
may / might: May refers to factual or possible; might is appropriate for the hypothetical or counterfactual.
nauseous / nauseated: To be nauseous is to cause sickness. To be nauseated is to feel sick.
people / persons: People has assumed primacy; persons is reserved mostly as a synonym for bodies (“those belongings carried on their persons”).
persuade / convince: To persuade someone is to motivate them to do something; to convince someone is to lead them to understand or believe.
repetitive / repetitious: Both terms have acquired a negative connotation, but the former retains a more neutral meaning.
sensual / sensuous: Sensual has an erotic connotation; sensuous refers more neutrally to what is pleasurable to the senses.
stationary / stationery: To be stationary is to stand still; stationery refers to letter-writing materials.
tortuous / torturous: A tortuous experience is a winding one; a torturous one is painful.
[use] the ampersand when the rest of the name is also an abbreviation (AT&T)
otherwise, use “and”
source : Ampersand : Grammar Girl
How to Make Names With Apostrophes Possessive : Grammar Girl :: Quick and Dirty Tips ™
It’s technically correct to write
or but it’s better to avoid either one.McDonald’s’s
McDonald’s’
It’s “Whom to Follow,” Twitter. W…H…O…M
There is a simple trick to knowing the difference between who and whom. All you have to do is answer your question or restate the sentence using “he” or “him”. This trick also works with whoever and whomever!
he = who/whoever
him = whom/whomeverExamples:
Who went to the circus?
He went to the circus. Therefore, who is correct.Whom should I ask about the discount?
You should ask him about the discount.

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