并列连词

用法

例句

and

表并列或顺承关系

He came into the classroom and put his schoolbag on the desk.

用于“祈使句，and +陈述句”结构

Be careful, and you will make fewer mistakes.

or

意为“或者”，表示任选其一

Do you want to go the zoo or the museum?

意为“否则”，用于“祈使句，or +陈述句”结构

Please be quick, or we will miss the last bus.

so

表示因果关系

It’s raining heavily now, so we have to put off the P.E class.

for

表示原因，及附带理由

I must be off now, for it is getting late.