So, To, Because.

I am studying this topic ____ I can understand it perfectly

I am studying this topic ____ I need to understand it perfectly.

I am studying this topic ____ understand it completely.

My boss called me ___ he wanted a better report.

• to

• so

• because

My boss called me ___ I could help him with something.

• to

• so

• because

My boss called me ___ congratulate me

• to

• so

• because

I'm studying English ____ I can get a promotion.

• to

• so

• because

I'm studying English ____ improve myself.

• to

• so

• because

I'm studying English ____ I need it to graduate.

• to

• so

• because

I go to the movies ____ entertain myself