免得 (shěng de) so as to avoid

Usage:

“省得”的意思是避免让某事发生，一般是指不好的事儿或某种不必要的情况。“省得”常用在后一个分句中，前面的分句大多表示建议或者劝说。也可以作“免得”。
"省得(shěng de)" means to avoid something from happening. Normally the thing here indicates to either a bad incident or something unnecessary. "省得" is usually put in the latter clause, and the former one is always about a suggestion or a persuasion. "省得" can also be equivalent to "免得".

Sentences:

1、Wǒ bǎ dōngxi dài guòlái le, shěngde nǐ zài pǎo yí tàng le.
我把东西带过来了，省得你再跑一趟。
I brought the thing here so spare you another trip.

2、Kuài gàosu fùmǔ ba, shěngde tāmen zháojí.
快告诉父母吧，省得他们着急。
You'd better inform your parents as soon as possible so that they won't get worried.

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