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在3dsmax中克隆对象需要按住键加鼠标左键进行拖拽。

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promoted left resulting appliancesbenefitedpaying average couples gains commonreflecting founddistribution impatience profitIn the U.S., John Robinson, professor of sociology at the University of Maryland, and Geoffrey Godbey, professor of leisure studies at Penn State University 1 that, since the mid-1960s, the average American had gained five hours a week in free time — that is, time 2 after working, sleeping, commuting, caring for children and doing the chores.The 3 , however, were unevenly distributed. The people who 4 the most were singles and empty-nesters. Those who gained the least — less than an hour — were working 5 with pre-school children, perhaps 6 the trend for parents to spend more time nurturing their offspring.There is, of course, a gender issue here, too. Advances in household 7 may have encouraged women to take 8 jobs: but as we have already noted, technology did not end household chores. As a result, we see appalling inequalities in the 9 of free time between the sexes. According to the Henley Centre, working fathers in the U. 10 48 hours of free time a week. Working mothers get 14.

在数据表中可以创建的约束有1、2、3、4、5、6。

创建表约束的方法有3种,第一种是在新建表时,在1之后创建约束;第二种是在新建表时,在2之后创建约束;第三种是表已经存在,可以通过3添加约束。

在一个表中只能定义1个主键约束,但可以定义2个唯一性约束;定义了唯一约束的列数据可以为3值,而定义了主键约束的列数据为4值。