嘧啶核苷酸从头合成途径中直接合成的核苷酸是
A．AMP B．UMP C．IMP D．GMP E．CMP
参考答案：B
《机动车安全运行技术条件》中规定，救护车的车身应为白色，标志灯具为( )。
A．红色回转式 B．蓝色回转式C．紫色回转式 D．红褐色回转式
It is wise to forget such things as aren't worth _____. [ ]
A. remembering
B. being remembered
C. to remember
D. to be remembered
