Question

Заполните пропускт,употребив глагол to be в правильной формет a)John_a student. b)It_cold today c)Cars_expensive d)I_happy e)Mary and Jane_from Canada

Answer 1

Is
is
are
am
are

That's very easy: John = singular noun, third person (is), "It" is a singular pronoun, third person ("is"), "Cars" is a plural noun (are), I is a first person singular pronoun (am), Mary + Jane is a coordination (plural), so we use "are". 

Answer 2

a) John is a student. b) It is cold today. c) Cars are expensive. d) I am happy. e) Mary and Jane are from Canada.