For example you might have the following two sentences:
- The meeting will start at 2 pm tomorrow.
- It will be in the large conference room on the 2nd floor.
These sentences can each stand alone, but the ideas are related, so you might wish to join them.
Because they are independent clauses, it is regarded as wrong to join them with a comma. This is what is called a comma splice.
- The meeting will start at 2 pm tomorrow, it will be in the large conference room on the 2nd floor.
To be grammatically correct, if you wish to join them, and you don’t wish to use a coordinating conjunction (remember FANBOYS – for, and, nor, but, or, yet, so), you have three choices:
- Join them with a semicolon
- Write two separate sentences
- Rewrite the clauses so they form one sentence
So the correct sentence will be:
The meeting will start at 2 pm tomorrow; it will be in the large conference room on the 2nd floor.
The meeting will start at 2 pm tomorrow. It will be in the large conference room on the 2nd floor.
The meeting, which will be in the large conference room on the 2nd floor, will start at 2 pm tomorrow.
Another example
Comma splice (incorrect)
The photocopier often malfunctions, however management has so far refused to replace it.
Correct
The photocopier often malfunctions; however, management has so far refused to replace it.
And another example
Comma splice (incorrect)
In 2010 the firm’s profit was up 10 percent from the previous year, by 2013 it had tripled.
Correct
In 2010 the firm’s profit was up 10 percent from the previous year. By 2013 it had tripled.
Remember . . .
In sum, the rule is that if the two parts of the sentence can stand alone, you need something stronger than a comma to join them.
Happy writing.