题干
More and more parks ________in Mentougou in five years.
A：build
B：built
C：will be built
D：were built
答案(点此获取答案解析）
C
More and more parks ________in Mentougou in five years.
A：build
B：built
C：will be built
D：were built
以角速度ω做匀速转动，则线圈从图示位置转过90°的过程中，下列说法正确的是 （ ）