我不敢在公开场合说英语，因为我的语音、语调很糟糕，英语成绩很差，语法一塌糊涂。

I dared not speak English aloud in public because of my poor pronunciation and intonation. I could not get high marks and grammar was not right at all.

youdao

例如，教育考试成绩证书当我做的很差，但我的家人并没有抛弃我，继续给我学习的机会。

For example, Certificate of Education Examination results when I do poorly, but my family did not abandon me, and continue to give me the opportunity to study.

youdao

我的成绩马马虎虎，不是很好也不是很差。

My score is so-so, not too good or too bad.

youdao

I've got a really bad grade on my test.

我在一门测试中考了一个很差的成绩。

I'm sure 实战 - SpeakingMax英语口语达人