Помогите!!!!!! Напишите 5 примеров с артиклями a и an. Пожалуйста!!!!!!!

a book  a pen  a car  a desk  a chair an apple an umbrella  an hour  an engineer  an omelette 

My mother is a sales manager. I need an umbrella. There is a white book on the table. London is a very beautiful city. Have you got an apple? My sister is a student. He left half an hour ago.