Excuse is simple, school text books.

借口很简单，学校收取教材费。

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By 2016, the average American high school senior said they spent six hours a day writing text messages, on social media, and online during their free time.

截至2016年，美国高中高年级学生说他们在空闲时间里平均每天要花6个小时的时间写短信、上社交媒体以及上网。

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Students should wear school uniform and bring the text books to school on that day.

学生须穿著校服，并于当日带课本到学校。

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(Speaking in Russian) Stelmakh says a look at school text books being published in Ukraine,the Baltics, and in other post-Soviet republics shows them to be attempts to distance those countries from Russia -- especially with regard to courses in national history.

VOA: standard.2009.12.25

Parents and guardians will be given updates about the reopening of the school via the its text messaging service and its website, a spokesman said.

BBC: Loxdale Primary School Bilston shut after metal thefts

Back in 1998, I remember marveling at high school students choosing to text one another rather than make phone calls, updating their friends with their "status" and even taking pictures with their mobile phones.

ENGADGET: This is the Modem World: Japan is not weird

It is economics 101, that every school child with an economics text book will read.

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