fatal error, called to undefined function, wp_cache

My blog has been running for almost a year with no problems, then all of a sudden I get an error message, but I have not changed anything or even posted recently.

Original error
Fatal error call to undefined function wp_cache_init(); on line 133 in wp-settings.php

I do some reading and research and find the advice to add the line

(‘ENABLE_CACHE’, true);

Above the line wp_cache_init(); in the wp_settings.php file

I do this and now I get this error:
Parse error: syntax error, unexpected ‘,’ in /home/merrfit8/public_html/wp-settings.php on line 131

I remove the comma from before the word true);

I now get the error:

Parse error: syntax error, unexpected T_STRING in /home/merrfit8/public_html/wp-settings.php on line 131

(Which from all I have read indicates a missing apostrophe or semi-colon. )

Upon further reading, I now edited this line in wp-settings.php to read

Define (‘ENABLE_CACHE’, true);

I added a directory called cache under wp-content and gave the permissions 777

The error message comes back to;

Fatal error: Call to undefined function wp_cache_init() in /home/merrfit8/public_html/wp-settings.php on line 131

Can anybody give me any assistance? My webhost said I need to re-install wordpress.
Thanks so much.