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

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".