The girl had hardly rung the bell __________ the door was opened suddenly, and her friend rushed out to greet her.
With a lot of difficult problems ____, the manager felt worried all the time.
As we all know, it was _____ that resulted in the terrible car accident.
In order not to be disturbed ,I spent three days in my study.
With online course Crazy English has over 20 million students all over China the class through the Internet .
He sat back on the chair, took a book and began to read, ___.