Never before in greater need of technical experts than it is today.
A. has Hunan been B. Hunan has been
C. was Hunan D. Hunan was
It is only people know the importance of science science can really serve the people.
A. that； when B. when； that C. then； that D. that； then
Sorry， I didn’t hear you. I to the music.
A. just listened B. was just listening C. has just listened D. had just listened
The fact has worried many scientists the earth is becoming warmer and warmer these years.
A. what B. which C. that D. though
If one succeed， one must put his heart into his career.
A. will B. is going to C. is to D. is about to
The book was written in 1946， the education system has witnessed great changes.
A. when B. during which C. since then D. since when
