消防报警控制系统由（）警铃和应急广播组成。
A.火灾探测器
B.消防专用电路
C.消防通道示意图
参考答案：A, B
用括号内单词的适当形式填空。
1. Line A is (long) than Line B.
2. Circle A is (small) than Circle B.
3. I have two apples. One is big but the other is (big).
4. My sister is (thin) than Lucy.
Jane _____ these families of chimps for many years and helped people understand how much they behave like humans.
A．had studied
B．studied
C．studies
D．has studied
