【单选题】【消耗次数：1】
15. While I like the dress very much, I cant afford it. The word “while” means ______.
①
when
②
although
③
as long as
④
whereas
参考答案：
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相关题目
【单选题】
The Apple Watch is very beautiful, but its too expensive. So I cant _____ it.
①
save
②
support
③
offer
④
afford
【单选题】
A: I like this flat very much, but Id like to come and see it on Friday at 5 oclock. Will that be convenient? B: [填空].
①
Its good for you
②
Thats right
③
Its thoughtful of you
④
Thats fine with me
【单选题】
I found the article while I was （ ） some old magazines.
①
browsing through
②
looking into
③
staring at
④
watching out
【单选题】
I fell and hurt myself while I ________ basketball yesterday.
①
was playing
②
am playing
③
play
④
played
【单选题】
The first time I [填空] to Yunnan,I liked it very much.
①
come
②
came
③
comes
④
coming
随机题目
【多选题】
令 F(x): x 是汽车, G( y): y 是火车, H(x, y): x 比 y 跑得快，则命题“说所有的火车比所有的汽车跑得快是不对的”符号化不正确的有：
①
x$y(F(x) ù G( y) ? H(x, y))
②
$x$y(F(x) ù G( y) ù H(x, y))
③
xy(F(x) ù (G( y) ? H(x, y)))
④
$xy(F(x) ù G( y) ù H(x, y)).
【判断题】
设 p: 2+3=5. q: 大熊猫产在中国. r: 复旦大学在广州. 则复合命题公式“(pùqù?r) ? (( ?pú?q) ?r)”的真值为假。
①
正确
②
错误
【判断题】
自然数里，a=2，f (x,y)=x+y，g (x,y)=x·y，F (x,y): x=y。公式“xy(F(f(x,a),y) ?F(f(y,a),x))”的真值为假。
①
正确
②
错误
【多选题】
设函数f: Z?Z, 若x为奇数f (x)=1, 若x为偶数f (x)= x/2，则下面正确的有：
①
f(1) = 1;
②
f({1}) = {1};
③
f({1, 3}) = {1};
④
f({1, 3}) = 1.
【多选题】
个体域为整数集, 公式“x$y(x×y = 1)”翻译成自然语言，下面合适的有
①
“每个整数都有一个倒数.”
②
“对于每个整数, 都能找到另一个整数, 它们相乘结果是1.”
③
“对任意非零整数, 都能找到另一个整数, 使得它们相乘结果等于1.”
④
“对于任意整数 x, 都存在整数 y, 使得 x×y = 1.”