Lesson 15: The lights in the meeting room were left on
Environmental Awareness and Energy Conservation
This lesson focuses on environmental issues, energy conservation, and sustainable living practices. Students learn expressions for describing unchanged states, explaining what things are good for, and discussing environmental actions. The lesson covers vocabulary related to recycling, energy saving, and eco-friendly practices in daily life.

Key topics:
- ・Describing unchanged or continuous states
- ・Discussing environmental conservation practices
- ・Explaining purposes and benefits of actions
- ・Energy saving and recycling vocabulary
- ・Sustainable living practices
Vocabulary
Conversation
Kanji
Grammar Rules
Rule 1: V-たままです
Used to describe a state that continues without changing, even though it should have ended. It emphasizes that something was left as is, often unintentionally or abnormally.
Rule 2: V-るのにいいです
Used to say that something is suitable or useful for a purpose. For example, 'good for the environment' or 'good for saving energy' — the noun + にいい changes into a verb form.
Exercises
Question 1
Choose the correct form to complete the sentence meaning 'The lights in the meeting room were left on.'
かいぎしつのでんきがついた______でしたよ。
Question 2
Choose the correct reading of 分けます.
ケーキを4つに______。
Question 3
Choose the correct form to complete 'Carrying your own straw is good for reducing waste.'
マイストローは、ごみをへらす______いいんですよ。
Question 4
What does 温度 mean?
きょうはおんどがひくいです。
Question 5
Choose the correct form to complete 'Last night, I fell asleep with the TV on.'
きのうのよる、テレビをつけたまま______。
Question 6
Choose the correct reading of 出します.
ゴミをそとに______。
Question 7
Choose the correct form to complete 'This app is useful for checking train transfers.'
このアプリはでんしゃののりかえをしらべる______べんりです。
Question 8
What does 設定 mean?
スマホのせっていをかえます。
Question 9
Choose the correct form to complete 'Please do not enter with your shoes on.'
くつをはいた______、はいらないで下さい。
Question 10
Choose the correct reading of 消します.
でんきを______。
Question 11
Choose the correct form to complete 'Eco bags are good for reducing plastic bags.'
エコバッグは、レジぶくろをへらす______いいです。
Question 12
What does 危険 mean?
ここはきけんなばしょです。
Question 13
Choose the correct form to complete 'The window was left open all night.'
まどがあいた______、よるをすごしました。
Question 14
Choose the correct reading of 種類.
いろいろな______のすしがあります。
Question 15
Choose the correct form to complete 'This textbook is good for learning Japanese.'
このきょうかしょは、にほんごをまなぶ______いいです。
Question 16
What does 捨てる mean?
ふるいしんぶんをすてます。
Question 17
Choose the correct form to complete 'He went out without eating breakfast.'
あさごはんをたべない______、でかけました。
Question 18
Choose the correct reading of 燃えます.
このかみはよく______。
Question 19
Choose the correct form to complete 'This website is useful for checking the weather.'
このウェブサイトは、てんきをしらべる______やくだちます。
Question 20
What does 決める mean?
りょこうのけいかくをきめました。