阅读下面短文，在空白处按要求填入适当的单词或括号内单词的正确形式。
Layla and her family were driving to the town park. It was a hot day. She wanted to swim in the lake. As they got out of the car, Layla saw ____ (she) friends.
"Let's go into the water!" she called. All the kids jumped in ____ (happy).
Layla always has fun at the park. In spring, Layla's dad often takes her fishing in ____(冠词) lake. They usually go early in the morning. The lake water is still (平静的). It is different ____ (介词) the river, which has water that runs by
In summer, ____ (family) have picnics near the lake. The kids play and swim in the lake.
In the morning of autumn, the lake has fog (雾) over it. Layla's dad once____ (tell) her something about fog: Hot summer days warm the water, and then cool autumn air ____ (move) over the lake's warm water. The water vapor(水蒸汽) in the air gets cool. It ____ (become) small drops of water (水珠). We can see those drops of water hang in the air as fog.
Layla loves winter at the park too. The cold ____ (temperature) turn the water into ice. Many people go skating on the ice.
The lake looks different at different times of the year, ____ (连词) it is always a good place to have fun!
pC(g)，达到平衡后，保持温度不变，将气体体积缩小到原来的一半，当达到新平衡时，C的浓度为原来1.9倍，下列说法错误的是