don't be afraid of asking for help_____it is neededAunless Bsince Calthough Dwhen
问题描述：
don't be afraid of asking for help_____it is needed
Aunless Bsince Calthough Dwhen
答
D。。
当你需要帮助的时候不要害怕寻求帮助。。
答
D
答
最好选D,B,D都有既然的意思,但是B 在时态上不如D好,