夏天在农贸市场卖海鲜产品的摊位上，经常看到摊主将冰块放在新鲜的海产品上面用于保鲜，这主要是因为冰块有较低的温度和熔点，且冰在 ____ （填一物态变化名称）过程中要 ____ 热量（选填：“吸收”、“放出”）．
①爷爷下棋。（在哪儿？和谁？）
②我们在教室里听课。（在什么样的教室里？怎样听？什么课？）
I w____ to Qingdao with my parents last summer holiday. We t____a plane there. We went to the beach. It was very b ____. I like swimming very much. I s____in the sea. My mum took many p____ there. We had a good time.
97前面的数是98，后面的数是96。
关节活动起来非常灵活，与之有关的结构特点是关节结构里有（ ）
