Ⅰ.用“介词＋关系代词”填空
1．Through the course of my schooling, I met many teachers, two ________ ________ have influenced me greatly.
2．The age ________ ________ children can go to school is seven.
3．This kind of colourless gas ________ ________ we can't live is called oxygen.
4．The dog, ________ ________ she used to be afraid, is her favourite animal now.
5．Have you ever had a case ________ ________ you are lost in a strange land?
