1. Visitors have been asked to keep the woods clean and tidy.
    游客已被告知要保持树林的整洁。

2. Make sure that all bottles are opened in your presence, and that their rims are clean and dry.
    确保瓶子是当你面开启的，瓶口清洁干燥。

3. Clean the glasses until they shine.
    把眼镜擦亮.

4. Our classroom is very clean.
    我们的教室很干净.

5. It cuts a clean cylinder of rock, from which can be seen the strata the drill has been cutting through.
    它切割出一块表面光滑的圆柱体石头, 从这石块上可以看出钻头在切割的岩层.

6. It cuts a clean cylinder of rock, from which can be seen the strata the drill has been cutting through.
    这种钻头能切割一段光滑的圆柱形岩石，从中能看出所钻透的地层。

7. Its wool, which had been dyed black, had been washed clean by the rain!
    原来羊毛上染的黑色被雨水冲掉了！

8. I become faster and neater each day. I'm outdoors in clean air. And, contrary to what people think, I don't get dirty on the job.
    我越干越快，越干越利索。在室外干活还可以呼吸新鲜空气。而且完全不像人们认为的那样，我干的活儿其实很干净。

9. It's a clean sweep
    吸尘器 挺管用

10. It is also important to have something that can clean water and kill bacteria, so water from other sources can be made safe to drink.
    储备一些可以净化水和消灭病菌的东西也很重要，这样就可以安全饮用其他来源的水了。