Too is an adverb. It is used before adjectives without nouns and before adverbs.
- I arrived too late.
- You are too generous.
Too and too much
Too much cannot be used before adverbs and adjectives without nouns.
- She is too fat. (NOT She is too much fat.)
Too with other determiners
Too is not normally used before adjective + noun.
- I could not lift the bag because it was too heavy. (NOT I could not lift the too heavy bag.)
- I could not solve the problem – it was too difficult. (NOT I could not solve the too difficult problem.)
Structures with too
An infinitive can be used after too + adjective / adverb.
- It is too hot to go out.
- He is too old to work.
If the infinitive has its own subject, it is usually introduced by for.
- It is too early for the shops to be open.
Note that object pronouns are not normally used after the infinitive in this structure.
- The tea is too hot to drink. (NOT The tea is too hot to drink it.)
Note that object pronouns can be used in structures with for.
- The tea is too hot for us to drink. OR The tea is too hot for us to drink it.
Too and very
Too is different from very. Too has a negative meaning. It means ‘more than enough’ or ‘more than is wanted’.
- She is very beautiful. (NOT She is too beautiful.)
- He is very intelligent. (NOT He is too intelligent.)
In informal English, too is sometimes used to mean ‘very’.
- That was too kind of you. (= That was very kind of you.)