植被的破坏容易引发泥石流，对泥石流的防治工作，我们可以做一些力所能及的事．下列行为不恰当的是（　　）

下列关于乙酸的说法中，正确的是（　　）

①乙酸易溶于水和乙醇，其水溶液能导电　

②无水乙酸又称为冰醋酸，它是纯净物

③乙酸分子里有四个氢原子，所以它不是一元酸　

④乙酸是一种重要的有机酸，常温下乙酸是有刺激性气味的液体　

⑤1mol乙酸与足量乙醇在浓硫酸作用下可生成88g乙酸乙酯

⑥食醋中含有乙酸，乙酸可由乙醇氧化得到．

阅读题， 判断下列句子正误,。正确的写“T”,错误的写 “F”.

John: Excuse me, can I use your ruler, please?

Amy: Sure. Where is my ruler?

John: Is it in your book?

Amy: No, it isn't.

John: Is it under the desk?

Amy: No.

John: Is it on your bag?

Amy: Yes, Look! It's on my bag. Here you are!

John: Thank you.

①The ruler is John's. ____

②The ruler is in Amy's book.____

③The ruler isn't under the book.____

④John wants to use the ruler.____

⑤The ruler is on John's bag.____

下列说法正确的是（     ）