state – declare – announce 宣布，声明
regret – sorry 遗憾的
remove – get off 脱下
start – begin 开始
observe -- stick to 遵守
previous – former 以前的
maintain – hold – think 认为
cause – bring about – lead to – result in 导致
error – mistake 错误
component – ingredient – element 成分
solve – settle 解决(问题)