我们从屋顶的小洞能看见星星。We could see the stars through an opening in the roof.蛀虫将我的羊毛衫蛀蚀了几个小洞.The moths have eaten holes in my wool coat.请缝补一下我袜子上的小洞.Please darn the hole in my sock....
Alkanes are resistant to attack by oxidizing agents generally.烷烃一般对于氧化剂的作用是稳定的.The general uses of alkanes may be divided into three categories.烷的一般用途可分为三个方面.The straight - chain alkanes exacerbate the problem of engine ...