Answer :
The correct spelling of night + time is nighttime.
Nighttime is a compound noun, formed by two nouns.
A compound noun can be an opened, hyphenated, or closed word.
In general, compound nouns formed by noun + noun are written as closed words.
If the last consonant of the first noun is the same as the first consonant of the second noun, both consonants are kept.
This is why nighttime is a closed word with a double consonant.
The same occurs with:
- lamp + post→ lamppost
- ear + ring→ earring
You can learn more about compound nouns in the link below:
https://brainly.com/question/26461656
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