You can use there is or there are for singular or plural elements. Remember that those expressions have the same meaning in Spanish (hay) .
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| There is a butterfly in the country (hay una mariposa en el campo) |
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| There are two mandarines on the table (hay dos mandarinas sobre la mesa) |
let's see there is or there are in questions affirmative and negative form
Affirmative:
there are three green frogs.
Negative: there aren't yellow frogs.
For simple questions you use:
Questions: Are there three green frogs?
Answers: Yes there are / No there aren't
