You must take heed and not be careless of your associations.

你必须小心，不要随便与人结交。

youdao

O 4 Very particular about the materials used: Lettering should be good to use TangLi -wood, must not be careless.

用材有讲究：刻字须用上好的棠梨木，决不能马虎；

youdao

"It is very careless of mother," said that young scoundrel John, "not to be here when we come back."

“妈妈太粗心了，”那个小坏蛋约翰说，“我们回来的时候她不在这儿。”

youdao

In my opinion, award the equity and be generous with key employees (which is absolutely not to say be careless).

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Similarly, drivers responsible for more serious examples of careless driving, such as those involving collisions, would not be given fixed penalty notices.

BBC: Fixed Penalty Notice motoring fines may rise to ?90