To master a foreign language like English requires hard work, so you can't study too hard.

掌握一门像英语这样的外语需要勤奋学习，因此你再怎么努力也不为过。

youdao

It is simply a fantastic imagination to conceive that one can master a foreign language overnight.

幻想在一天早晨就把外语学好，那只是白日作梦。

《新英汉大辞典》

It's not easy to master a foreign language.

掌握一门外语并不容易。

youdao

You can appreciate how impressive this is only if you have attempted to master a foreign language yourself.

FORBES: A New International Business Language: Globish