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言う， 云う， 謂う， いう， ゆう
1. to say, to utter, to declare
2. to name, to call
3. to go (e.g. "the alarm went ping"), to make a noise
说，宣读，声明；称呼；发出(例如：警报响了‘叮’的一声)，发出声响
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足す， たす
1. to add (numbers)
2. to add (something), to top up (with something)
3. to take care of (e.g. one's business)
添加(数字)；添加(某物)，补充(某物)；打理(如自己的事务)
は
1. indicates sentence topic
2. indicates contrast with another option (stated or unstated)
3. adds emphasis
指示句子的主题；表示与另一选项（无论是否明确提及）形成对比；表示强调
