If you're chatting online, or sending text messages to a good friend, it doesn't really matter how you knock out the words. But when you're writing an essay for school or completing a job application, be sure not to make any of these common mistakes that really irk uptight people. I know of managers who will bin a job application immediately if they see such errors.
Definitely most definitely should not contain the letter a. Anywhere. Ever.
It is very common to see any one of these words incorrectly substituted for any other of these words. The problem is that these three words sound almost exactly the same, but mean very different things:
These three are pronounced differently by most people, but are still similar enough to be mixed up frequently.
Could've is the contraction of "could have". It should never be written "could of".
The apostrophe is frequently misused. People mistakenly use the apostrophe in plural words, but it is really only used to indicate abbreviation and possession.
When a word or phrase is abbreviated by removing letters, the apostrophe is used to mark where the missing letters used to be. (If two words are combined into one, this is called a contraction.)
The apostrophe can also be used to indicate that something belongs to someone or something. This is done by adding an apostrophe and an s after the word that represents the someone or the something, and is known as the possessive form. Examples will probably be the clearest explanation.
When the possessing word already ends in an s, the apostrophe goes after the s. This most often occurs in plural words (words that name a group of persons or objects).
Regarding possessing words that already end in s, some people prefer to use an apostrophe followed by another s. This is usually when the possessive form of the word would be spoken with an extra s sound.
Apostrophes should not be used to form a plural word. A plural is a word that denotes more than one of something. The word "apple" is singular, and "apples" is the plural.
Advertisements abuse percentages all the time. There is a big difference between percentage of and percentage increase. Don't trust a company's claims unless you see the numbers yourself.
If we have two numbers, X and Y, and we want to know how much X is as a percentage of Y, you divide X by Y and multiply by 100.
Example: say that the Illustrative political party get 3,467 votes in an election, and that the total number of votes in the election was 19,523 votes. If we divide 3,467 by 19,523 and then multiply the result by 100, we get 17.76 (to two decimal places). So we say that the Illustrative party got 17.76 percent of the total number of votes.
Example: the HappyTrolley supermarket sells a textbook for £14.99, and the BulkBook store sells the same book for £8.97. If we divide 8.97 by 14.99 and multiply the result by 100, we get 60 (to the nearest whole number). So we say that you can buy the textbook at BulkBook for 60 percent of the price you'd have to pay at HappyTrolley. The saving you'd make is £6.02, and 6.02 divided by 14.99, then multiplied by 100, is 40 (to the nearest whole number). So you've saved 40 percent of the price you'd have to pay at HappyTrolley.
Example: internet hosting company 2&2 have increased the webspace included in their basic webhosting package from 100 megabytes to 150 megabytes. If we take 150 and divide it by 100, then multiply the result by 100, we get 150 exactly. So the new webspace allowance is 150 percent of the previous amount.
To work out what percentage an amount has increased by, we look at the new value N and the previous value P. Then do N minus P, then divide the result by P, then multiply by 100. If the result is positive, then there has been a percentage increase; if the result is negative, then there has been a percentage decrease.
Example: say that the Illustrative political party got 2,386 votes in the last election, and this time they got 3,467 votes. If we do 3,467 minus 2,386 we get the difference which is 1,081. If we divide this by 2,386 then multiply the result by 100, we get 45.31 (to two decimal places). So we say that the Illustrative party saw a percentage increase of 45.31 percent over last election's result.
Example: to keep up with competition, HappyTrolley has reduced the price of a textbook from £14.99 to £9.97. To find the percentage change in price, we do 9.97 minus 14.99 to get a difference of -5.02 (notice that it's a negative number). If we divide this by 14.99 and multiply the result by 100, we get -33 (to the nearest whole number). So there has been a price decrease of 33%. This will no doubt be plastered all over the item on the shelves in big, brightly-coloured stickers.
Example: internet hosting company 2&2 have increased the webspace included in their basic webhosting package from 100 megabytes to 150 megabytes. If we do 150 minus 100 to get a difference of 50, then divide that by 100 and multiply the result by 100, we get 50 exactly. So the alloted webspace has increased by 50 percent, not by 150 percent.
Get It Write Online, which features an archive of grammar and writing style tips.
Grammar tips from the Purdue University Online Writing Lab.
Oxford Dictionaries Online, a free online dictionary, and sections about better writing.
Guide to Grammar and Style, by Jack Lynch. Features an a-to-z listing of English grammar and writing elements.