─ Mrs. Zhang was sent to teach English in a poor mountain village last year.
─ She said she would never forget some pleasant ______ while working there.
A：experiments
B：expressions
C：experiences
D：emotions
人的性别决定是在（ ）
— Yes. Many visitors are surprised at the rapid ________ of Fuzhou.
当今世界的竞争是科技竞争,国防建设对科技的要求越来越高。导弹部队的建立就是适应这一趋势的结果。我国的导弹部队组建于 ( )
解方程组： {x+2y=53x−2y=−1
