1.50 USAGE NOTE

Note that the words 'bacteria', 'data', and 'media' are now often used as collective nouns, that is with either a singular or a plural verb and no change in form. Some careful speakers think they should only be used with a plural verb because they have the rare singular forms 'bacterium', 'datum', and 'medium' and are therefore count nouns.

• Medieval Arabic data show that the length of the day has been increasing more slowly than expected.
• Our latest data shows more firms are hoping to expand in the near future.