To improve your knowledge in every subject you should or you must go on a way full of drills .These drills we can call or name them exercises or practise .As a matter of fact or a question of curiosity these kind or sort of tasks are essential parts .In Maths if you don t practise the rules with different types of exercises..and so on for the rest of subjects. In languages these drills occur in speaking in oral communications such as dialogues or conversations ..we called them The Input it s taught at the beginning of every file or unit during the teaching English for beginners at middle school level classes ..also these drills can be seen in Reading such oral and written questions and in Grammar it is seen in exercises in practice objectives and the last course writing and this through substitution and confirmation so bye saha sehorkem and we shall meet tommorow in chalah