It happened when I was in Grade Four.

这件事发生在我四年级的时候。

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I'm a pupil in Grade Four.

我是一个四年级的小学生。

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I ran outside to gossip with my friends who were in my grade four class.

我跑到外面去和我四班的朋友聊天。

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Mr. MONTY NEILL (Co-Director, National Center for Fair and Open Testing): While scores have tended to go up on NAEP at grade four--and in math they went up fairly solidly for a while--they've now leveled out.

NPR: Mixed Report Card for U.S. Schools

One plan is to split the A grade into four sub-categories.

ECONOMIST: Exams

The average scores were categorized at each grade level into four groups: below basic, basic, proficient, and advanced.

CNN: Report card shows U.S. students need to improve math skills