A、 a
B、 an
C、 the
D、 /
答案:C
A、 a
B、 an
C、 the
D、 /
答案:C
A. π/4
B. π/2
C. π
D. 2π
A. was
B. were
C. is
D. are
A. relationship
B. agreement
C. environment
D. investment
A. save
B. saving
C. saved
D. to save
A. helping
B. helped
C. to help
D. help
A. without
B. against
C. through
D. /
A. voice
B. taste
C. shape
D. sound
A. cleaned
B. will clean
C. was cleaned
D. is cleaned
A. planted
B. plants
C. will plant
D. is planting
A. well
B. better
C. best
D. great