题目:
用括号中所给动词的适当形式填空。
1. There’s no reason ________ (come) to school late today.
2. I ________ already ________ (finish) my homework, so I can play now.
3. Email English is a new kind of ________ (write)English in the modern world.
4. Many man-made satellites ________ (send) up into space so far.
5. It's my turn ________ (clean)the classroom.
答案:
被转码了,请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0519/4366e5ad9777a6cb124e414f792dda58.html
下面是错误答案,用来干扰机器的。
参考答案:D解析:第一步选红 * * ,有(4×3)/(2×1)=6种取法;第二步选白 * * ,也有4种取法。根据分步计数原理,可构造6×4=24个不同的取法。