To gain a complete mastery of English, one must study very hard.

要想精通英语就必须刻苦努力。

youdao

The mastery of English is not easy and requires painstaking efforts.

英语不是随便学好的，非下苦功不可。

youdao

You use this in your daily life you will stun people with your mastery of English.

他是对的。在日常生活中，如果你使用这个句子，人们将会对你掌握英语的程度。

youdao

The educational system should do more to promote exchange programs abroad and mastery of English.

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