The room was so quiet that she could hear the _____ of her heart.
When first____ to the market, these products enjoyed great success.
That art center is _______ used to be a factory, ______ millions of tractors were produced.
--- Have you finished the report? --- No. I ______ it all this week.
Last week, only two people came to look at the house, ____ planning to buy it.
Wherever he goes, he readily _______ to new circumstances.