I had just started back for the house to change my clothes _____I heard my name called.
A. as B. for C. while D. when
It is an interesting story and one can't put it down _____ one has finished reading it.
A. after B. when C. since D. until
I have been keeping the portrait _____ I can see it every day, as it always reminds me of my childhood in Paris.
A. since B. where C. as D. if
_____earth scientists understand how and why earthquakes happen, forecasts are usually inaccurate.
A. As B. While C. Because D. If
Mr. Smith wanted to buy the house and he told me that ____the house cost，it would be worth it.
A. however B. how much C. whatever D. what
I was so excited last night that it was a long time _____I got to sleep.
A. that B. since C. before D. when
