Passage TwoQuestions 26 to 30 are based on the following passage.In our day of the automobile and paved highway few people ever encounter quicksand(流沙). Yet quicksand is still common in many pans of the country. It may be more dangerous for being less fam
题目
Passage Two
Questions 26 to 30 are based on the following passage.
In our day of the automobile and paved highway few people ever encounter quicksand(流沙). Yet quicksand is still common in many pans of the country. It may be more dangerous for being less familiar.
Quicksand is usually found along the shores and in the beds of rivers. It is simply sand saturated(使饱和)with water from beneath，as from a spring. The water flowing into the sand separates the grains. The suspended grains give rather easily and a heavy object placed on the surface is likely to sink. How fast it sinks depends on its weight and surface area.
How does one detect quicksand? It cannot be done by the eye alone，since sand which looks firm may suddenly collapse and trap anyone who ventures out on it. The only way to be sure is to test the sand before walking on it. For test a probing(探索)pole or long stick should be used. If the pole sinks more than six inches，the sand is probably quicksand.
A traveler who stumbles into quicksand will soon sink to the depth of his knees. If he stands still or struggles wildly，he will sink even further. He should at once lie on his back and stretch out his arms. Contrary to popular notion，quicksand does not suck objects down，and will support more weight than water alone. While the trapped person “floats” on the surface of the sand，rescuers should build a platform. with boards or branches. Then they can pull him out slowly.
If the trapped person is alone，he can rescue himself. When he is in the floating position，he should begin rolling toward solid ground. Rolling is the only way of getting free. It should be done with frequent rests，so that the trapped person does not tire himself. When he reaches solid ground，he should swing his legs to safety，and quickly scramble out of the quicksand.
The main idea of this passage is______.
A. that today few people ever encounter quicksand
B. that quicksand is still common in many parts of the country
C. that quicksand cannot be detected by the eye alone
D. expressed by none of the above
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第1题：
有以下程序includeusingnamespacestd;static int days []={31,28.31,30,31,30,31,31 有以下程序 #include ＜iostream＞ using namespace std; static int days []={31,28.31,30,31,30,31,31,30,31,30,31}; class date { private: int month, day, year: public: date (int m, int d, int y { month = m; day = d; year = y; } date{} {} void disp {) { cout ＜＜year＜＜" - "＜＜month＜＜ "- "＜＜day＜＜end1; } date operator+(int day) { date dt = *this: day += dt.day; while { day ＞ days[ dt.month - 1 ] ) { day -= tays[ dt.month - 1 ]; if ( ++dt.month == 13 { dt.month = 1; dt.yeare++; } } dr. day = day; return dt; } }; int main() { date d1( 6, 20, 2004 ), d2; d2.= d1 + 20; d2.disp (); return 0; } 执行后的输出结果是
A．2004-7-10
B．2004-6-20
C．2004-7-20
D．程序编译时出错
正确答案：A
解析：本题考核运算符的重载。本题通过将“+”运算符重载为类date的成员函数实现简单的对象加法。 -
第2题：
有以下程序includeusing namespace std;static int days []={31,28,31,30,31,30,3l,3 有以下程序 #include＜iostream＞ using namespace std； static int days []={31,28,31,30,31,30,3l，31，30,31，30,31}； class date { private： int month，day，year； public： date(int m，int d，int y) { month=m； day=d； year=y； } date() {} void disp() { cout＜＜year＜＜"-"＜＜month＜＜"-"＜＜day＜＜end1； } date operator+(int day) { date dt=*this； day+=dt.day； while(day＞days[dt.month－1]) { day-=days[dt.month-1]； if(++dt.month==13) { dt.month=1； dt.year++； } } dt.day=day； retrn dt； } }； int main() { date d1(6，20，2004)，d2； d2=d1+20； d2.disp()； return 0； } 执行后的输出结果是
A．2004-7-10
B．2004-6-20
C．2004-7-20
D．程序编译时出错
正确答案：A
解析：本题考核运算符的重载。本题通过将“+”运算符重载为类date的成员函数实现简单的对象加法， -
第3题：
后缀-our的语义和形容词性物主代词our是相同的，表示“我们的”。
错误 -
第4题：
有以下程序:includeusingnamespacestd;staticintdays[]={31,28,31,30,31,30,31,31,30 有以下程序： #include ＜iostream＞ using namespace std； static int days[]={ 31，28，31，30，31，30，31，31，30，31，30，31 }； class date { private： int month，day，year； public： date( int m，int d，int y ) { month = m; day = d; year = y; } date() {} void disp() { cout＜＜year＜＜"-"＜＜month＜＜"-"＜＜day＜＜end1; } date operator+( iht day ) { date dt = * this; day += dt.day; while ( day ＞ days[ dt.month - 1 ] ) { day -= days[ dt.month - 1 ]; if ( ++dt.month == 13 ) { dt.month = 1; dt.year++; } } dt.day = day; return dt; } }; int main() { date dl( 6, 20, 2004 ), d2; d2 = dt + 20; d2.disp(); return 0; } 执行后的输出结果是( )。
A．2004-7-10
B．2004-6-20
C．2004-7-20
D．程序编译时出错
正确答案：A
解析：本题通过将“+”运算符重载为类date的成员函数实现简单的对象加法。类date中的“+”运算符重载函数中，将传入的实参值day，加到类date的私有成员变量day上，并实现变量month和year的相应变化，从而达到日期对象相加的目的。 -
第5题：
Under defense plans，operation of electronic aids may be temporarily suspended with ______．
A.one day's notice
B.no notice
C.thirty（30）day's notice
D.a week's notice
正确答案：B
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第6题：
5、后缀-our的语义和形容词性物主代词our是相同的，表示“我们的”。
错误