Using more

More is a modifier. It is used in a variety of situations.

In comparatives

Adjectives of more one syllable form their comparative forms with more. Examples are: more beautiful, more intelligent and more careful. Note that longer adjectives ending in –y tend to have comparative forms ending in –er. Example: happy -> happier; merry -> merrier
More is used to express the idea that there is more of a particular quality.

Tokyo is more populous than Beijing.
She is more beautiful than her sister.

Less is the opposite of more. It is used to indicate that there is less of a particular quality.

• Cricket is more popular than tennis in India.
• Tennis is less popular than cricket in India.

More as a determiner

As a determiner more serves the same purpose as an adjective: it is used before a noun.

• We need more time to finish the job.
• My wife earns more money than I do.
• Could I have some more potatoes?

Note that before a pronoun or a noun with a determiner (e.g. articles, possessives and demonstratives) we use more of.

• She is more of a genius than I thought.
• Five more of the missing pilgrims have been found.
• He is more of a nuisance that you might think.

After more, we use a plural noun.

• More people now access information on the internet.
• It is important to include more fruits and vegetables in your diet.

More can also be followed by singular uncountable nouns.

• Could I have some more rice?

More without a noun

More can be used alone without a following noun if the meaning is clear. For example, you are having dinner. The hostess might ask if you need more referring to rice, soup, fish, water etc. If the meaning is clear from the context, the noun can be dropped in this case.

• Would you like some more, please?

Note the structure number + more + noun + infinitive.

• I have three more semesters to go.
• She requires six more credits to graduate.
• We will need two more weeks to finish the job.

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