tolong di jawab ya, pliss

1. (-) my english teacher isn't in front of the class
(?) is my english teacher in front of the class?

2. (+) they give their congratulation to me
(-) they don't give their congratulation to me

3. (+) sam and i come to sarah's house
(?) do you and sam come to sarah's house?

4. (+) my brother whires a letter for me
(-) my brother doesn't whires a letter for me

5. (-)my brother's friends aren't visit our house
(?) are your brother's friends visit your house?