_If__ _you___ use your head,you'll find a way.
【解析】这里考查“祈使句+ and/or+一般将来时的句子”,其中前半句相当于一个if引导的条件状语从句.
如：work hard and you'll succeed.=If you work hard ,you'll succeed.(从句是肯定句时用and）
Hurry up ,or you'll be late.= If you don't hurry up,you'll be late.（从句是否定句用or）