如图所示的四种现象中,属于光的反射现象的是[ ]
A.
B.
C.
D.
答案:D
DNA彻底水解后可得到的物质是[ ]
A.氨基酸
B.氨基酸和脱氧核苷酸
C.二氧化碳、水和含N废物
D.脱氧核糖、含N碱基和磷酸
用所给单词的适当形式填空。
1.I am going to _______ (learn) music next year.
2.He _______ (teach) us English last term.
3.Don't _______ (throw) the stone at me.
4.Christmas is very important in _______ (west) countries.
5.I forget _______ (bring) this book for you. Here you are!