Question: Following is the combination of words that I need to search and replace:

```
[Cc]ontestants:
[Cc]ontestants :
[Cc]ontestant:
[Cc]ontestant :

```

Is following correct?

```
'/[Cc]ontestant(:| :|s:|s :)/'

```

The sentence (or line) will start with the word and end with : (with or without a blank space before :) followed by some other words in the sentence, or no words after :. 

Just need to match and replace the above combination with a new word - say MyWord.

Thanks.

Answer: 
You may reduce it to,

```
[Cc]ontestants?\s*:

```

or

```
[Cc]ontestants?\h*:

```

> 
> The sentence (or line) will start with the word and end with :
> 
> 
> 

If it's at the start then use start of the line anchor `^`

```
^[Cc]ontestants?\h*:

```
If the line starts and end as described I suggest the following:

```
^\[Cc\]ontestants?\s?\:$

```

The "$" at the end ensures that there are no further characters after the ":". I.e. `[Cc]ontestant:d` wouldn't match.