ANSWERS PROVIDED 40 sentences to practice There is, There are, It is, They are.
Look out for countable / uncountable. Remember - when there is a list, there is / there are depends on the FIRST item in the list. So it´s "There is an apple and 2 bananas" but "There are 2 bananas and an apple".
You can find more practice tasks at http://www.englishshouldbefun.com/basics-there-is-there-are/