如图所示，理想变压器原副线圈匝数之比为4：1，原线圈接入一电压为u=220sin

回答问题1和问题2。

用所给词的适当形式填空。

     I have many pen pals in many 1_____ (country). Do you know the girl on the bike in the photo?

She is one of my pen 2_____ (pal). Her name is Reiko. She is a Japanese student. We have the same

age 13 years old. She 3_____ (live) in Tokyo. She 4_____ (have) two brothers. They live with their

parents.

     I like Reiko very much.  But I don't know 5_____ (Japan), and Reiko 6_____ (not know) Chinese.

But we know English. So we 7_____ (write) letters in English. Sometimes we talk on the phone. My

favorite subject is math. 8_____ (she) favorite subject is music. We have the same 9_____ (hobby).

We like seeing comedies, playing volleyball and 10_____ (eat) hamburgers.

因特网作为一种硬力量，是一种技术、载体和平台，它可以使

具有单性花的科是：

A．麻黄科

B．马兜铃科

C．马鞭草科

D．唇形科

E．百合科

毛坯的塑性变形区绝大多数受到两向以上的作用可以用硬化趋向或用硬化曲线函数来表示。