No. "Author" isn't a proper noun; it's a thing, like "person" or "employee." Mark Twain would be capitalized, because his name would be considered a "proper noun," like "Earth" versus "planet."
No, an apostrophe should not be used after a number to indicate possession. Use an apostrophe before the "s" to show possession (e.g., the dog's bone).
No, you do not need to put an apostrophe in the word "hundreds" unless you are indicating a contraction or possession.
Yes, you would put an apostrophe after the z when making it possessive. For example, "The dog's leash" would be correct.
The apostrophe in "children" would be placed before the "s" to show possession: children's.
The apostrophe in "cyclist" would be placed before the last letter when indicating possession: cyclist's.
The hammer of neither doesn't require an apostrophe.
after the t (it's) You put an apostrophe on 'its' if it's a contraction of "it is." Otherwise, 'its' has no apostrophe because that's its nature.
Put the apostrophe in mices right after s.: mices'
No apostrophe is to be putted in this sentence.
Personally, no. But it's not incorrect to put the apostrophe.
"Volkswagen" doesn't require an apostrophe.
no matter what you usually have to put a period after an apostrophe because it's the end of a sentence.
Aren't- The apostrophe replaces the 'o' in this circumstance.
I'd
won't (:
No.
we'll
No, you do not need to put an apostrophe in the word "hundreds" unless you are indicating a contraction or possession.