马大哈  (mǎdàhā) a careless person

Usage:

“马大哈”指做事马虎、粗心、草率的人。对很多事情都无所谓，比较随便，爱忘事。本词最早来源于“马马虎虎”“大大咧咧”“嘻嘻哈哈”三个词的组合。
"马大哈(mǎdàhā)" refers to those who are careless and hasty. They hold a casual attitude towards most of the things and are forgetful. This phrase is a combination and abbreviation of the three words “马马虎虎(mǎmǎ huhu)”, “大大咧咧(dàdà lielie)” and “嘻嘻哈哈(xīxī haha)”.

Sentences:

1、 Nǐ zhège mǎdàhā, yòu bǎ yàoshi nòng diū le.
你这个马大哈，又把钥匙弄丢了。
You lost your key again; you are so careless.

2、 Chūqù lǚyóu yào kānhǎo zìjǐ de xíngli ,búyào dāng mǎdàhā.
出去旅游要看好自己的行李，不要当马大哈。
Do not be a scatterbrain and leave your luggage unattended when you are traveling.

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