They were surprised that a four-year-old boy should work out such a difficult problem ____ they themselves couldn’t.
We should keep ourselves_______ of the latest development of science and technology.
To those_______ in martial arts(武术), the period from 1972 to 1975 is often said_______ the Bruce Lee era.
Though_______ money, his parents managed to send him to university.
After he retired from office, Rogers_______ painting for a while, but soon lost interest.
The first visit to the Great Wall with my parents gave me a deep_______.