已知$△ABC$的外接圆半径为R，角$A$、$B$、$C$的对边分别为$a$、$b$、$c$且$2R\left({\sin }^{2}A-{\sin }^{2}C\right)=\left(\sqrt{2}a-b\right)\sin B$，那么角$C$的大小为        （      ）                             

已知集合M={2，3，4}，N={0，2，3，4，5}，则∁_NM=（　　）

3个9相加得____，再加上2个9得____。

世界上绝大多数动植物在我国都能找到适合生长的地区，这主要是因为我国（　　）

    I started to learn English when I was six. My dad gave me1advice on listening to the Beatles. I listened to them every day for the next seven years. At the beginning, I could understand2of what they sang. But soon I started to understand some of the3.

    4 I got a book with the words of all the songs. And when I had time, I would read it. I learned many songs5this book. I6the songs to myself. Still, I understood very7of the meaning. To learn English well became my8, and I wanted to learn the9of the Beatles' songs. That is how I started to learn English.

    Today, I can understand the Beatles very10. Each time I hear a Beatles' song, I am happy and proud because my dream of learning English well has come true.