单选题 根据下面资料，回答21-35题。
Mrs.McTavish looked out."It's a lovely day.Would you like to go for a walk in the park？"Her children 21 with excitement.
"Before we go， you need to follow some rules.Everyone must 22 hands and stay close to me.You can' t 23 anywhere by yourself.Can you all do that？"
All four 24 they would.As they walked down the street， Fiona said，"I want an ice lolly（冰棍）， Mummy.Can we have some？"
"You can if you follow the rules，" answered Mrs.McTavish.
The park is just around the corner.The children ran off to 25 After a while， when Mrs.McTavish looked up she couldn' t see Jock."Fiona， where' s Jock？"
"I don' t know， Mummy.He' s not here 26 ，" said Fiona.
The others hadn' t 27 Jock either.Mrs.McTavish had to gather her children together and walk
around the park 28 for him.She found him sitting near the ice lolly man."Jock ! What are you doing
here？ I couldn' t 29 you."
"Mummy， I want an ice lolly， "Jock whispered.
"You can't have one now 30 you didn't follow the rules."Mrs.McTavish 31 one for each of the other children and they licked （~，） them all the way home.Jock cried.When they 32 home she talked to Jock."Mummy has four children.I must have rules so I can 33 an eye on you
and know you' re 34 ."Jock said he was 35 and he would follow the rules from then on. 第（30）题选