21、Lin Guangzhao is a student at Shenzhen Yucai School．These days，when he arrives at or leaves school，his parents know it at once．Is Lin being watched by his parents? No，the secret is a small card Lin uses．The blue card looks nothing special，but in fact it is a smart card．It has Lin's name，student number，blood type （血型） and picture in it．

"When a kid punch （刷卡） the card at the school gate，a mobile phone message is sent to his or her parents，" explained Xu，a school gatekeeper．"The message is like：Dear Mum and Dad，I've arrived at/left school．"

This term，about 10 Shenzhen schools have begun to use or plan to use this kind of smart card．"Schools hope the card will make students safer．Besides the information on attendance （出勤），teachers can use the card network （网络） to tell parents about their kids' performance．"

Parents are fond of the card．Some students like it，too．Li Hengyi，16，finds the card useful．"Days ago a typhoon （台风） hit out city．I punched the card and my parents to came to take me home very soon．"

But other students，like Mai Min，are uncomfortable with the card．"I used to play sport after school，" said Mai．"Now with the card，I have to call nay parents to tell them about it every time．"

根据短文内容，判断下列陈述的正（T）误（F）。

1．When Lin arrives at school，he always sends a message to his parents using a mobile phone．

2．The smart card is helpful to students' safety．

3．Teachers can use the card network to tell parents about their kids' performance．

4．About 10 schools plan to use this kind of smart card this term．

5．Not all students are pleased with the card．