When not to use です


さくらは青い = Sakura is blue

さくらは青いです also = Sakura is blue

Google use the first one as default. How do we know when it's ok not to use
desu?




If you're a beginner, this is the general rule: add です after any adjective or
noun in formal sentences if the verb is "to be". In informal sentences, the
verb "to be" is not です, but だ, and you can choose to say it or omit it in both
nouns and な-adjectives. With い-adjectives (like this case), you can't say だ,
so you always omit it.

