Сделайте предложения отрицательными, вопросительными и ответ на вопросительное предложение: the teacher (to give) the task to the student . тут на время , настоящее время. тут также с вопросом и отрицанием. без ! your sister (to be) at school.

Present Simple.
The teacher gives the task to the student . 
The teacher doesn`t give the task to the student . 
Does the teacher give the task to the student? Yes, she does.
Past Simple.
The teacher gave the task to the student .
The teacher didn`t give the task to the student . 
Did the teacher give the task to the student? Yes, she did.
Present Simple.
Your sister is at school.
Your sister isn`t at school.
Is our sister at school? Yes, she is.
Past Simple.
Your sister was at school.
Your sister wasn`t at school.
Was our sister at school? Yes, she was.