老掉牙 (lǎo diào yá) very old; out of date; obsolete

Usage:

“老掉牙” 形容事物、言论等陈旧过时。常用作定语。
“老掉牙” means sth. or speeches are out of date. It often acts as an attribute.

Sentences:

1、Nǐ néng bu néng bù tí zhèxiē lǎo diào yá de shìqing, tīngzhe jiù fán!
你能不能不提这些老掉牙的事情，听着就烦！
Can’t you speak of the business out of date, which makes me irritable?

2、Guānyú tā de xīnwén yǐjīng lǎo diào yá le.
关于他的新闻已经老掉牙了。
The news about his was too old.

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