A：Parks are really important in a neighborhood. ____

B：Sounds good.What can we do?

A：Well, we can pick up garbage(垃圾)．

B：What a great idea! ____

A：Yes, let's ask them to come.We can ask the neighbors, too.

B：____

A：We should bring garbage bags and buckets(水桶)．

B：____

A：Let's volunteer on Saturday.The weather will be sunny.

B：____ 

A：Wear old clothes.We'll probably get dirty.

B：OK.I will tell the others.

A．People must keep them clean.

B．When should we volunteer?

C．What should we wear?

D．Maybe we can invite our friends to help.

E．Let's volunteer to clean up Central Park.

F．I learned a lot from the activity.

G．What should we bring?

尺规作图“作一个角等于已知角“的依据是三角形全等的判定方法____．

Thank, Mum.

反应mA（s）+nB（g）⇌pC（g）△H＜0，在一定温度下，平衡时B的体积分数（B%）与压强变化的关系如图所示，下列叙述中一定正确的是（　　）

①m+n＞p　

②x点表示的正反应速率大于逆反应速率　

③x点比y点时的反应速率慢　

④n＞p　

⑤若升高温度，该反应的平衡常数增大．