选出下列各组词语中字形有错误的一项并改正（  ）。

阅读理解

 Dear Grandma,

    Thank you for the new shorts. They are cool! It's hot in Beijing. It's sunny too. I can wear my shorts and T-shirt. I have a new jacket. My old jacket is too small. I want to buy a hat. It is fifty yuan. It's too expensive.

   What's the weather like at the farm? Is it warm? How many new ducks are there?

                                                                                                                                                                 Love

                                                                                                                                                                 John

测试场景时，下列说法正确的是（   ）

图中“→”表示血管内血液流动的方向，其中可确定为静脉的有（    ）