题干
A group of children ______ hide and seek in the garden.
A：is playing
B：are playing
C：has been playing
D：was playing
答案(点此获取答案解析）
B
A：is playing
B：are playing
C：has been playing
D：was playing
的值的一个程序框图，其中判断框内应填入的条件是（ ）
