题干

把磨得很光滑的铅片和金片紧压在一起,在室温下放置5年后再将它们切开,可以看到它们互相渗入约1mm深,表明固体之间也能发生____现象;将两个铅柱的底面削平、削干净,然后紧压在一起,两个铅柱就会结合在一起,甚至下面吊一个重物都不能把它们拉开,主要是因为铅柱的分子之间存在____。
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根据短文内容及所给首字母提示写出所缺单词,使短文意思完整,每空一词。

    When you have dinner, you follow table manners. When you have a l____ , you obey the rules in the classroom. But have you ever thought about needing to m____ your manners in the digital(数码的) world when you use phones, e-mails and social media, like QQ, WeChat, etc?

    As new research by Oxford University noted, "It's just important to treat people with respect online as it is in real life." The study came up with some rules of good manners to live by in the digital age. Their first a____ is not "over-sharing" on social media, which means not posting every detail about your life online, because some of us are not creative e____ to always show off our thoughts and lives on social media.  The manners also i____ not looking through others' phones and not gossiping(说闲话) about others over messages, e____ when you choose "reply all" to send a message to a group of people.

    Although gossip is not h____ chat that can make conversations exciting, it can also be a way to spread something untrue about other people. Gossip can be even stronger on social media than in real life, so it's b____ not to gossip.

    Moreover, when you have bad news for someone, do not leave text messages on social media, chat with him or her by c____ personal messages.

    Nowadays, technology has o____ us different ways to contact others. It is important to remember how to behave toward others online.