( )(1)There are some ducks on the pond.
![](http://static.xuejinqu.com/qimg/f7b/f7b64a22e979b09a1c5b0b63077905fa.png)
( )(2)I am eating my sandwich.
![](http://static.xuejinqu.com/qimg/661/66181548a3068e2ad9bdb904f139dbaf.png)
( )(3)It’s raining today.
![](http://static.xuejinqu.com/qimg/eab/eabdd9ce342a94023c5d4ef618e96e4e.png)
( )(4)We have a picnic in the park.
![](http://static.xuejinqu.com/qimg/b0b/b0b3baaee5ff77fa96a7ab37fa90cd3e.png)
( )(5)He is playing football.
![](http://static.xuejinqu.com/qimg/42a/42a1c6f849dd759bf905b58cf1402a79.png)
![](http://static.xuejinqu.com/images/y-prise.png)
同类型试题
![](http://static.xuejinqu.com/images/medal.png)
y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
![](http://static.xuejinqu.com/images/avatar.png)
![](http://static.xuejinqu.com/images/avatar.png)
y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
![](http://static.xuejinqu.com/images/avatar.png)
![](http://static.xuejinqu.com/images/avatar.png)