1. The class was so noisy, so the teacher couldn't hear the question. ( since )
Since the class was so noisy ,the teacher couldn't heard the question
2. Jean will come home tonight. I'll give her your message. ( as soon as )
3. My sister was washing up yesterday evening. She broke a plate. ( while ) 
My sister was washing up yesterday evening while she was broking a plate
4. We are going to make an early start. We don't want to get stuck in the traffic. ( so .... that )
We are going to make so early start that we don't want to get stuck int he traffic
5. The telephone rang. The baby woke up. ( when )
When the telephone rang,the baby woke up