A teacher wanted her students to learn vocabulary effectively. Which of the following ways should she adopt to teach vocabulary in her classroom ?

1. Write all the new words on the blackboard and write their meanings in the language of teaching.
2. Ask her learners to underline the difficult words in a lesson and find their meanings in their language,
3. Ask them to find the meanings of the words in the dictionary.
4. Ask them to group the words into meaningful categories and use them in real life purposes.