1. He has been wearing glasses ever ____ he entered the university. 

　　　 A) when
　　　 B) while
　　　 C) since
　　　 D) once

　　2. _____ fire burns, there must be oxygen. 

　　　 A) Wherever
　　　 B) As soon as
　　　 C) Until
　　　 D) Before

　　3. You may turn to me for help ____ you are in difficulty. 

　　　 A) till
　　　 B) where
　　　 C) since
　　　 D) whenever

　　4. No sooner had I got there ____ a storm began. 

　　　 A) than
　　　 B) when
　　　 C) after
　　　 D) before

　　5. ____ the temperature increases, the volume of a substance becomes greater. 

　　　 A) While
　　　 B) As
　　　 C) Since
　　　 D) Till

　　6. Stormy applause（暴风雨般的掌声）broke out ____ he finished his speech. 

　　　 A) while
　　　 B) since
　　　 C) the minute
　　　 D) the day

　　7. On and on he went, _____ he reached a small village. 

　　　 A) when
　　　 B) as
　　　 C) once
　　　 D) till

　　8. _____ there was trouble, there he was sure to be. 

　　　 A) When
　　　 B) Where
　　　 C) As
　　　 D) Every time