To "lose something" in English means to no longer have something because you do not know where it is or because you cannot find it. This phrase comes from the verb "to lose," which means to suffer the loss of something, either through misplacement or forgetting.

Here are some examples of this phrase in use:

I can't find my keys anywhere! I must have lost them.

Please help me look for my phone. I don't want to lose it.

I didn't mean to lose your book. Can you help me find it?

In Chinese, "丢东西" (diū dōngxi) means to lose something, with "丢" (diū) meaning to throw away or discard and "东西" (dōngxi) meaning things or objects. This phrase is often used to refer to losing small items like keys or a phone.

Here are some examples of this phrase in use:

我找不到钥匙了，一定是丢了。 (Wǒ zhǎo bú dào yàoshi le, yīdìng shì diū le.) - I can't find my keys anywhere. I must have lost them.

请帮我找手机。我不想把它丢了。 (Qǐng bāng wǒ zhǎo shǒujī. Wǒ bùxiǎng bǎ tā diū le.) - Please help me look for my phone. I don't want to lose it.

我不是故意丢掉你的书的，你能帮我找找吗？ (Wǒ bùshì gùyì diū diào nǐ de shū de, nǐ néng bāng wǒ zhǎo zhǎo ma?) - I didn't mean to lose your book. Can you help me find it?