Grammar 101, ... or, pet peeves Options

[agrippa]

Here's a place for us to bore eachother to death about grammar. I'll go first.

I. POSSESSIVES AND PLURALS

Most nouns are made plural by the addition of 's' or 'es'.
computer -> computers
house -> houses

Some nouns have irregular plurals.
mouse -> mice
fish -> fish

A noun is never made plural with an apostrophe.

The apostrope and 's' are used to show possession.
Ron's (belonging to Ron)
Ginny's (belonging to Ginny)

However, pronouns have their own possessive forms:
his (belonging to him)
hers (belonging to her)
theirs (belonging to them)
its (belonging to it; it's means 'it is')

[agrippa]

"I am a wizard," Neville said tentatively, "but not a very good one."

That's correct. The problem with the other:

"I am a wizard," Neville said tentatively.  "But not a very good one."

is that "But not a very good one" is a sentence fragment (big no-no!) because it doesn't have a subject. MsCat is right is saying that it's "implied" - which is a fancy way of saying "we all know what he means" - but it's still technically incorrect.

Almost all punctuation goes inside the quotation marks.

"What did you say?" asked Harry.
Seamus said, "I love playing the lowland pipes."

One exception is the semicolon.

This charm is called the "protean charm"; the name comes from the Greek shape-shifting sea-god, Proteus.

That help anyone?