In Greece, children, even when middle-ag...to their boundaries.

哪种晶界能有效阻止滑移并且增加材料强度? A: small-angle grain boundaries B: twin boundaries C: big-angle grain boundaries D: large grains

‌哪种晶界能有效阻止滑移并且增加材料强度?‍ A: small-angle grain boundaries B: twin boundaries C: big-angle grain boundaries D: large grains

There should be no national boundaries in _________ protection.

‎There should be no national boundaries in _________ protection.‏

The surroundings include everything external to the system，and the system is separated from the surroundings by the system boundaries.

In Greece, children, even when middle-aged, can assert themselves with their parents, and parents keep to their boundaries.

（）is a measure of the market value of all goods and services within the boundaries of a nation.

True or False: Determining the class boundaries of a frequency distribution is highly subjective.

The difference between international tourists and domestic tourists is whether they cross the national boundaries or not.