翻译:后来他渐渐明白了为什么他们的英语老师经常叫他们背诵课文。(come to

Later he came to understand why their English teacher often told / asked them to memorize / recite the texts.

注释：come to do sth. 渐渐……

Later he came to realise why their teacher always asked them to recite the texts.

At last he had gradually understood that why their English teacher often asked them to recite the text.

It was not until later that they came to understand why their English teacher constantly told them to memorize the textbook.

later,he guadually understand the reason that their English teacher ask them to learn the texts by heart.