我儿子的老师说他的作业常常相当粗心。

My son's teacher says that his work is often rather ___careless.

他关于她外貌的一个粗心评论让她真的很不高兴。

He made a ___careless remark about her appearance that really upset her.

总之，我们必须认识到粗心驾驶的危险，以避免或至少减少高车祸率。

In short, we have to realise the danger of ___careless driving, in order to avoid or at least to reduce the high rate of car accidents.