Lots or Plenty of and Singular Nouns
Lots and plenty are also quantifiers, as they both describe the quantity of the noun in the sentence. The terms lots or lots of both imply a quantity of more than one, while the terms plenty and plenty of imply enough and more. For example:
Lots of people learn a foreign language.
A lot of my friends live here
There is plenty of time.
Plenty of shops accept debit cards.
Both lots and plenty are used in affirmative sentences and can be placed before singular or plural countable and uncountable nouns.
Although lots and plenty are acceptable in academic writing their usage is considered to be informal. In formal academic writing, it is more appropriate to use many, much and more. These terms are always conjugated in the singular when referring to a specific noun, whether it is countable or uncountable. When referring to a general noun, or anything not specific, drop the of the after many, much or more. For example, reconsider the prior sentences:
Many of my friends live here.
Many shops accept debit cards.