I can well remember that there was a time _____ a deep blue sky,  the song of the birds,  moonlight and flowers could never have kept me spellbound. 

I was about to go to bed _____ one of my old classmates made a call to me.

.He said that not until the heavy snow blocked the express ______ how serious the weather was.

My sister was very afraid all the way because it was the first time she ______ a car.

 The reason why he was late is ______ he got up too late.