Question

you can not be careful with it

You can't do well in the exam if you___（not be） careful with it．

Answer 1

答案：aren't
根据该句为含有if引导的条件状语从句的复合句，其中主丛信句中含有情态动词can，当主句渗纯轮含有情态动词时，if引导的条件状语从句通常用一般现在时．根据从句的主语为you，故be动词为are，否定句在are后面加裤拦not，缩写为aren't，故答案为：aren't