Past Sipmle / Past Continuous 1. - The scientists (work) in their laboratory when they (discover) the new drug. 2.- We (climb) the wall when the gardener (see) us. 3.-Vicky (have) a beautiful dream when the alarm clock (ring) 4.- As he (run) for the bus he (collide) with a street lamp. 5.- When he (carry) a suitcase, he (drop) it on his foot. 6.- (you / do) your homework on the bus while you (come) to school? 7.- The students (read) the article when the last class (finish 8.- When I (arrive) at the cinema, my friends (wait) for me. 9.- (you / listen) to the teacher when she (explain) this exercise? 10.- Susan (play) the piano while Mary (sing).