To achieve full marks in English as a second language in junior high school, one should focus on the following aspects:

1. Vocabulary: Consistently expand your vocabulary by learning new words and phrases. Keep a dictionary or use digital resources to understand the meanings and correct usage of words.

3. Reading Comprehension: Improve your reading skills by reading various types of texts, such as novels, essays, and news articles. Pay attention to context clues to better understand unfamiliar words.

4. Listening and Speaking: Immerse yourself in English-speaking environments, such as watching English movies, listening to podcasts, or joining language exchange groups. Practice speaking aloud to improve pronunciation and fluency.

By focusing on these key areas and practicing consistently, you can aim for full marks in junior high school English exams.