液压蓄能器是用来为油系统蓄存能量的。
参考答案：对
Bob, _________ is Jenny. She is my friend.[ ]
A. he
B. she
C. this
The price of vegetables is＿＿＿＿＿than before．
A．much cheaper
B．even higher
C．still dearer
D．a lot more expensive
