________ the difficult maths problem, I have consulted Professor Russell several times.
The teacher will never have Tom away within the exam.
The two sisters are ________ different in character --- one talks a lot while the other is a girl of few words.
He has been in bed ______ he fell off his bike a week ago.
The letter he had been looking forward to________at last this morning.
______ is reported in the newspapers, talks between the two countries are making progress. (北京2004.34)