人说话时，把手指放在喉结处，会感到声带在____，发出的声音在空气中以____的形式传播；那些刺耳难听，令人厌烦的声音称为____．

两宋词坛的风格虽有豪放和婉约之分，这一时期许多词作中均流露出较为浓厚的忧患意识。这种忧患意识所反映的时代特征是(    )

根据短文内容和所给中文提示，写出空白处各单词的正确形式。每空限填一词。

    Jenny is an English girl. She is ____ (九) years old. Today is ____ (三月) 16th. It's her birthday. She wants to have a birthday ____（晚会）. It is ____ (在) seven this evening. But her uncle and aunt are____ (迟到的).She ____ (见面) five of her friends. They buy her a big birthday cake，two boxes of____ (牛奶), a basket of fruit, and ____ (一些) school things. Jenny wears a____ ( 绿色) sweater and brown trousers. She looks very nice. They all ____ (度过) a good time.

用一根长144cm的铁丝围成一个正方体框架，它的棱长是____cm。

下列实验操作会导致实验结果偏低的是                                                 
（1）配制100 g10％的CuSO₄溶液，称取10gCuSO₄晶体溶于90 g水中
（2）配制一定物质的量的浓度的H₂SO₄溶液，浓硫酸溶解后未冷却就立即转移入容量瓶进行定容
（3）配制一定物质的量的浓度的H₂SO₄溶液，定容时仰视容量瓶的刻度线
（4）实验室制取氯气，当二氧化锰足量且反应充分，利用收集到的氯气的物质的量求算出的浓盐酸的物质的量