1、reason作名词时,常用:
①The reason is that...;
②the reason why....如果先行词reason在从句中作主语或宾语时,则用that或which,不用why;
③by reason of由于……的缘故;
④for...reason/reasons由于……的原因;
⑤out of all reason不合情理;
⑥with reason有充分的理由。
2、reason与cause用法不同:reason侧重指某种看法或行为的理由,与for连用;cause侧重指某个事实或现象的原因,与of连用。
3、reason作不及物动词意为“评论”。