I have no difficulty __________ writing, but I have some difficulty __________ pronunciation.  

如图是人的呼吸、泌尿与血液循环关系示意图，字母表示相应的生理活动或器官，数字表示相应的管腔．请据图回答问题：

Exercise—It's good for you!

Playing sports，dancing and even touching your toes is exercise．Exercise builds a strong body．This helps you to do all the things you want to do．

⒈Exercise helps you to keep fit

Can you bend(弯腰)down and touch your toes? Can you stretch(伸展)up high? Exercise helps you to bend and stretch easily．

⒉Exercise makes you strong

Use your arms and legs often．Exercise builds strong muscles(肌肉)．

⒊Exercise makes you feel good

Running，jumping and playing with your friends is exercise．It makes you happy．

⑴为图片选择合适的编号，⑵⑶⑷根据短文内容，选择正确答案。