English Grammar Rules & Mistakes: Learn All of the Essentials: Writing, Speaking, Literature and Punctuation Rules Complete with 10 Key Skills and Over 200 Common Error Examples

such that in English. It is used to give more information or elaborate a
sentence. However, these two (i.e., and e.g.) may be used to clarify a
sentence, i.e., by explaining the sentence more or by illustration, and e.g.
explaining by citing examples. Note the following differences:
Drinking and driving is dangerous, i.e., the eyes become blurry, and the
cognitive orientation is affected too.
Drinking and driving is dangerous; it can cause a lot of damage, e.g., damage
to you and damage to the environment where it happens.
To say take note, or when you want to draw readers’ attention to an
important aspect of your writing, use P.S. Although commonly used in
corporate organizations in memos and other messages, when used in
noncorporate writing, P.S., from the words post script, is an effective
abbreviation tool for communcating.
Do not confuse the abbreviations for these three words: they’re, their, and
there.
Many a student makes the error of using they’re to mean they are, in English
grammar. While that may look fancy or interesting, it is nonstandard to use.
Desist from saying “they’re coming;” rather, use “they are coming.”
Another error students make is deriving the abbreviation ther’re from there
are. Think about this: can “ther’re” be substituted for “there are?” the answer
is no. It is nonstandard to use it in English grammar. If at all you wish to
make an abbreviation from the word "there," a standard acceptable way is to
shorten "is."
So instead of having there is, you can actually have there’s.
To avoid abbreviation errors when you are either writing or speaking, you
need to pay attention to the following commonly used abbreviations in
English grammar:
Use Mr./Mr and Mrs./Mrs/Ms. when you mean Mister or Missus,
respectively.

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The idea behind abbreviated Mister/Missus with or without the "dot"
connotation is that; "Mr/Mrs" without the dot is acceptable in British English
grammar, while Mr./Mrs. Is acceptable in American English grammar. 
Abbreviate the word appointment as appt., and never mistake it for apt.,
used for the word apartment"
When you see misc., it means miscellaneous.