Style Guide - Usage Issues

As - comma or no comma?
Used in the sense of “in that,” as needs to be preceded by a comma. She must work on her English, as this will help her move forward in class. Without the comma, it could be confused with as in the sense of time (“while” or “during”). He is working diligently as the year proceeds.


Beginning a sentence with and, but or other conjunctions
As Oxford points out, the ban on starting a sentence with and or but is a stylistic preference rather than a grammatical rule. Indeed, starting with a conjunction can help add drama or emphasis. So go ahead. But do so sparingly. See more at http://blog.oxforddictionaries.com/2012/01/can-i-start-a-sentence-with-a-conjunction/


Compound and simple sentences
Compound sentences are two independent sentences joined by and, but, or, etc. These require a comma between the clauses: Joe did well on his test, and I wish him luck in the future. Note that each clause could stand alone as a separate sentence.

A simple sentence doesn’t require a comma: Martha found the subject challenging and failed the final.

A handy trick is to see whether the verbs share the same subject (in this case “Martha found” and “Martha failed”). If so, there’s probably no comma necessary.

It seems like a small matter but the comma can help avoid confusion in a sentence: Martha promotes peace and hate will never be in her heart versus Martha promotes peace, and hate will never be in her heart.

Note 1: Canadian Press suggests that the comma may be omitted when the clauses are short. The gun boomed and the race went on.

Note 2: CP also suggests, “When in doubt, err on the side of too few commas.”


Double space between sentences
Do not.


Ending sentences with a preposition
Once considered a mortal grammatical sin, ending a sentence with a preposition is no longer taboo. In fact, contorting your sentence so that you don’t end with a preposition can make you sound pretentious. If it sounds natural, let it be. James wants to know which bus to get on.


False Series
There is a problem in this sentence: Today I will clean the bedroom, the living room and wallpaper the den. Break it down: I will clean the bedroom. I will clean the living room. I will clean wallpaper the den. That doesn’t work. Will tidy refers only to the bedroom and the living room. Wallpapering the den is another action altogether. Fix: Today I will clean the bedroom and living room, and then I will wallpaper the den; or: Today I will clean the bedroom, straighten the living room and wallpaper the den. (Example from www.quickanddirtytips.com/education/grammar/how-to-use-parallel-construction-correctly )


However
Avoid this: Daniel continues to improve, however, he is a long way from passing this course. What is the however referring to? Do you interpret the above as Daniel continues to improve, however, or However, he is a long way from passing this course? Make it two sentences: Daniel continues to improve. However, he is a long way from passing this course. Or reconstruct: Although Daniel continues to improve, he is a long way from passing this course.


Not only... but also
When using this type of structure, ensure that what follows not only is parallel to what follows but also.
No: Susan not only arrives early for class but also she stays behind when everyone is gone.
Yes: Susan not only arrives early for class but also stays behind when everyone else is gone.
No: The trees were not only colourful but also they were gigantic.
Yes: The trees were not only colourful but also gigantic.


Parallel structure
From https://owl.english.purdue.edu/owl/resource/623/1/
Strive to create parallel structures in sentences that include a series of actions.
Not parallel: The coach told the players that they should get a lot of sleep, that they should not eat too much and to do some warm-up exercises before the game.
Parallel: The coach told the players that they should get a lot of sleep, that they should not eat too much and that they should do some warm-up exercises before the game.
Or better still: The coach told the players that they should get a lot of sleep, not eat too much and do some warm-up exercises before the game.


That vs which
That introduces a defining clause, while which introduces a non-defining clause. If you can’t do without the clause to identify the subject, use that: Students must take courses that will lead to university acceptance. If the clause merely adds additional information about the subject, use which: Students may take the professional boxing option, which is offered every spring. There is usually a comma before which.