When we talk about amounts and quantities we usually use singular determiners, verbs and pronouns, even if the noun is plural.
- Fifty dollars is too much to lose. (NOT Fifty dollars are too much to lose.)
- Twenty miles is a long way to walk.
- Where is that ten pounds you borrowed from me? (NOT Where are those ten pounds you borrowed from me?)
Expressions beginning ‘one of’ are usually followed by a plural noun and a singular verb.
- One of my friends is going to Zambia. (NOT One of my friends are going to Zambia.)
Some expressions joined by and take a singular verb even though they may contain a plural noun. This usually happens when the two nouns are used together so often that we think of them as a single idea.
- Bacon and eggs was served for breakfast.
- Where is the cheese and biscuits?
The expression ‘more than one’ is normally followed by a singular noun and verb.
- He has got more than one reason to be unhappy.
- If things continue like this, more than one person is going to lose his job.
Countries having plural names (e.g. The United States of America, The United Arab Emirates) take singular verbs and pronouns.
- The United States of America is one of the most developed countries in the world.