开发区土地利用进行单项指标分级评分，可分为（）。
A.很适宜
B.基本适宜
C.适宜
D.不适宜
参考答案：A, B, C, D
A warm thought suddenly came to me ____ I might use the pocket money to buy some flowers
for my mother's birthday. [ ]
A. if
B. when
C. that
D. which
GSM数字蜂窝移动通信网根据不同情况可采用一下哪几种组网方式？（）
A.三级
B.两级
C.无级
D.四级
