选择方框里的单词，将短文补充完整。

 

sun   mountains   birds   river   flowers   what   rainbow   park   clouds   nice

    This is a nature ____ .There is a  ____ and some  ____ in the sky.There are two  ____ flying in the sky.Look! There is a beautiful  ____ between the two ____ .There is a long  ____ on the grass.There are some  ____ on the grass. ____ a  ____ picture it is!

选词填空。
（1）My sister ____ (will watch/watches) the basketball game at the gym tomorrow.
（2） ____ (Last Sunday/This Sunday), I went to the park.
（3）I ____ (helped/will help) my mother clean the rooms next Saturday.
（4） ____ (Who/When) went shopping with you?
（5）____ (Where/What) will his cousin go this summer holiday?

近五年来，我国在载人航天、探月工程、载人深潜、北斗卫星导航系统、超级计算机、高速铁路等方面分别取得了重大突破，同时，第一艘航母"辽宁舰"入列，歼一15战机顺利进行了起降航母的飞行训练……上述成就表明我国 （   ）

关于冰醋酸的说法中正确的是（   ）

下列物质长期暴露在潮湿的空气中，质量会增加且没有变质的是