As a teacher, it’s my duty to teach correct English to my students.

If you had called him that day, he would have helped you. 

He will get his house painted tomorrow (by a painter).
He will have his house painted tomorrow (by a painter).

Would you like me to play?

German Shepherd dogs have acute sense of smell.

Take off this t-shirt right away.

First, you get rid of your negative attitude, then only you can pass this so called tough exam.

He wants to learn.

He has a pen.

He has been doing this for days.