In order to know a foreign language thoroughly （完全地） , four things are necessary. Firstly, we must understand the language when we hear  spoken. Secondly, we must be able to speak it  (correct) with confidence and without hesitation（犹豫）.  we must be able to read the language, and fourthly, we must be able to write it. We must be able to make sentences that are grammatically correct.

    There is no easy way to success in language learning.   good memory is of great help, but it is not enough only  ( memorize) rules from a grammar book. It is not much use learning by heart long list of words and  meaning, studying the dictionary and so on. We must learn by using the language.  we are satisfied with only a few rules we have memorized, we are not really learning the language. “Learn through use” is a good piece of  (advise) for those  are studying a new language. Practice is important. We must practise speaking and  (write) the language whenever we can.