输入序列为ABC，可以变为CBA时，经过的栈操作为: push,pop,push,pop,push,pop|push,pop,push,push,pop,pop|push,push,pop,pop,push,pop|push,push,push,pop,pop,pop

输入序列为abc,若输出序列为bca,经过的栈操作为( ) A: push,pop,push,pop,push,pop B: push,push,push,pop,pop,pop C: push,push,pop,push,pop,pop D: push,pop,push,push,pop,pop

The store is __________(in front of / to the front) the park. A: in front of B: to the front

There is a tree ________the house. A: in front B: in the front of C: in front of D: on front of

设有一个空栈，现有输入序列1，2，3，4，5，经过push，push，pop，push，pop，push，push后，输出序列是_________

The bus stop is ________________ the gate. A: in the front of B: in front C: in front of D: at the front of

He is sitting __________ the classroom. A: at the front B: in the front of C: in front D: in front of

There<br/>is a tree ________the building. A: in front of B: in the front of C: in front D: in the front

设有一个空栈，现有输入序列为1，2，3，4，5，经过PUSH，PUSH，POP，PUSH，POP，PUSH，PUSH后，输出序列是 。

The square is just _____________________ of Bank of China. A: in front of B: in the front of C: at front of D: at the front of