Students often make mistakes with uncountable nouns. These are nouns that you can't count. Most importantly, they don't have a plural form.
For example, you can't say "an information, two informations, many informations". You can say "some information, more information, a lot of information, a piece of information".
Here are a few more uncountable nouns:
- give advice, some advice, a piece of advice (an advice, advices)
- do research, carry out research, research shows (a research, researches)
- gain knowledge, share knowledge, increase knowledge (knowledges)