已知函数f（x）=x²+2ax-1

（1）若f（1）=2，求实数a的值，并求此时函数f（x）的最小值；

（2）若f（x）为偶函数，求实数a的值；

（3）若f（x）在（-∞，4]上是减函数，那么实数a的取值范围．

用所给词的适当形式填空。

1. March 8th is _______ (woman) Day.

2. My brother enjoys _______ (take) a walk with his dog.

3. The bus trip is _______ (relax). 

4. The good news made us _______ (feel) happy.

5. They decided _______ (see) monkeys first.