行政许可的原则是哪些？

中低频段是声音的______，影响声音的力度和结实度，中低频不足时声音疲软，中低频过强时，声音生硬，产生嗡嗡声，影响清晰度。中低频______时，显得坚实、有力、丰满，其中100～250Hz频段具有良好的______。

Travel is      to us in at least three ways.

First,      We can see many places with our own eyes. We can visit some famous cities and scenic spots(风景区).

Second, we will meet people with different interests and see strange and different things when we travel. We can get ideas of the conditions and customs of other people, taste different foods and local flavours(风味) if we like. In this way, we can understand how differently other people live.

Third, travel will _______ help us to get knowledge of geography and history and other knowledge, _______ help us keep healthy and make us broad-minded(心胸开阔).

With all these advantages of travel, it is no wonder that travel has now become more popular than ever in China.

根据短文内容，按要求完成下列各题。

小题1: 在文中第一段的横线上填入一个恰当的词。_______

小题2:选择合适的句子填入第二段，使其语句通顺，符合逻辑。_______

A．by traveling we can see different people.

B．by traveling we can make friends.

C．by traveling we can enjoy the beautiful scenery of different places.

D．by traveling we can enjoy delicious food.小题3:在第四段的每条横线上填入两个恰当的连词，使句子完整。

______ ______

小题4:请把第五段中的“advantage”译成汉语。______

小题5:Which is the best title of this passage? ______

A．Traveling

B．Places of Interest

C．Advantages of Traveling

D．Disadvantages of Traveling

商检机构对进出口商品实施抽查检验时，应当公布抽查检验结果或者向有关部门通报抽查检验情况。（）

薄板制件常采用的焊接接头形式有哪几种？

球童起源于（）

A.法国

B.英国

C.苏格兰

D.美国