单选题 .  Some people seem to have a knack (诀窍) for learning languages. They can pick up new vocabulary, master rules of grammar, and learn to write in the new language much more quickly than other people. They do not seem to be any cleverer than others. What makes language learning so much easier for them? Perhaps if we take a close look at these successful language learners, we may discover a few techniques which make language learning easier for them.
    Firstly, successful language learners are independent learners. They do not depend on the book or the teacher; they'd rather discover their own way to learn the language than wait for the teacher to explain everything. They try to find the sentence patterns, the rules and the meaning of the new word by themselves. They are good guessers. They look for clues and form their own conclusions. When they guess wrong, they guess again. They try to learn from their mistakes.
    Besides, successful language learning is active learning. Therefore, successful learners do not wait for a chance to use the language; they look for such a chance. They find people who speak the language and they ask these people to correct them whenever they make a mistake. They will try anything to communicate. They are not afraid to repeat; they are willing to make mistakes and try again. When communication is difficult, they can accept information that is inexact or incomplete. It is more important for them to learn to think in the language than to know every word's meaning.
    Finally, successful language learners are learners with a purpose. They want to learn the language because they have an interest in the language and the people who speak it. It is necessary for them to learn the language in order to communicate with these people and to learn from them.1.  Successful language learners are independent, so successful learners ______.