AREFUL!
• Students make many errors when using the past continuous, often because the tense does not exist in their own languages. Instead, they may try to use past simple all the time and this can result in the wrong sequence of events, e.g.
I arrived at school. Jacky played a game with Ella. (Correct form = When I arrived at school, Jacky was playing a game with Ella.)
• Another mistake is for students to use the present tense of be in the past, e.g.
I am walking home yesterday when I saw a fast car. (Correct form = I was walking home yesterday when I saw a fast car.)