非常时期-------可读的书
https://www.newyorker.com/magazine/2020/03/30/life-on-lockdown-in-china 这是一篇成都封城日记，作者是纽约客的专栏作者，目前就职于四川大学，很有意思的观察和思考。
另外一个非常有用的链接，感谢大门同学，他是这个时代的先驱
感谢Bill Gates赞助，小孩子（和成人）又有免费阅读的资料了：
每个星期一本书：https://www.inc.com/justin-bariso/bill-gates-follows-4-rules-to-get-most-from-reading-books.html
书在下面这些链接：
https://archive.org/details/nationalemergencylibrary
三年级：https://archive.org/search.php?query=subject%3A%22Reading+Level-Grade+3%22
四年级：https://archive.org/search.php?query=subject%3A%22Reading+Level-Grade+4%22
五年级：https://archive.org/search.php?query=subject%3A%22Reading+Level-Grade+5%22
六年级：https://archive.org/search.php?query=subject%3A%22Reading+Level-Grade+6%22
七年级：https://archive.org/search.php?query=subject%3A%22Reading+Level-Grade+7%22
八年级：https://archive.org/search.php?query=subject%3A%22Reading+Level-Grade+8%22
九年级：https://archive.org/search.php?query=subject%3A%22Reading+Level-Grade+9%22
十年级：https://archive.org/search.php?query=subject%3A%22Reading+Level-Grade+10%22
十一年级：https://archive.org/search.php?query=subject%3A%22Reading+Level-Grade+11%22
十二年级：https://archive.org/search.php?query=subject%3A%22Reading+Level-Grade+12%22
成年：https://archive.org/search.php?query=subject%3A%22Reading+Level-Adult%22
下面是其他的免费书籍：
CK12:CK-12 Free Textbooks - Full K-12 Curriculum https://click.icptrack.com/icp/relay.php?r=115618670&msgid=656840&act=A5UQ&c=1125734&destination=https%3A%2F%2Fwww.ck12.org%2Fbrowse%2F
Barnes & Noble: https://www.barnesandnoble.com/b/free-ebooks/nook-books/_/N-ry0Z8qa
Amazon: https://www.amazon.com/b/?tag=freeblog022-20&_encoding=UTF8&node=2245146011&linkId=BNRPUFVEMRQP2NRR
Audible: Audible Free Audiobooks https://click.icptrack.com/icp/relay.php?r=115618670&msgid=656840&act=A5UQ&c=1125734&destination=https%3A%2F%2Fstories.audible.com%2Fstart-listen
Gutenberg: https://www.gutenberg.org/wiki/Category:Bookshelf
Read.gov: http://read.gov/books/
Library of Congress Digital Collections
https://www.loc.gov/collections/?fa=original-format%3Abook&st=gallery