It should be placed after the last s. Passengers'
they'd
No. Only letters, numbers and underscores.
He was researching where the correct place to put apostrophes is.
Yes, any decade requires apostrophes.
The word apostrophe forms a normal plural as apostrophes.The possessive forms would be:apostrophe's (singular) - "The apostrophe's use in contractions is fairly standardized."apostrophes' (plural) - "The apostrophes' positions are wrong in some of his words."
It all depends on how you use the term. If its plural (ex. how many officer are on the team??) then it doesn't have an apostrophised if its not (another ex. that officer's in trouble.) it would mean the officer is. So then it would have an apostrophes.
If the bicycles belong to ONE FRIEND, it's "friend's bicycles." If the bicycles belong to TWO OR MORE FRIENDS, it's "friends' bicycles."
In the possessive pronouns "theirs" and "hers," the "s" already indicates possession, so apostrophes are not needed. Including an apostrophe, such as in "theirs" or "her's," would be grammatically incorrect.
No words are contracted into apostrophes.
Inches is shown by two apostrophes (").
Possessive pronouns do not take apostrophes. Some examples of possessive pronouns are: its, hers, his, theirs.
Book titles should be italicized when typing, rather than using apostrophes. This helps to differentiate the title of the book from the surrounding text.