问题：
[多选题]Teachers can help learners take responsibility in vocabulary learning by_______, _______, _______, and providing encouragement and opportunity for learners to reflect on their learning and to evaluate them. ( )
Ainforming the learners of the different types of vocabulary
Btraining the learners in the various ways of learning vocabulary
Cproviding opportunities for learners to choose what to learn and how to learn
Dasking students to look up in the dictionary every new word they encounter in reading.
