suffer指一般的损害、痛苦等，其宾语为pain,loss,grief,insult,punishment,wrong等，但suffer from表示遭受战争，自然灾害带来的苦难及患病之意。
suffer的用法
1.感到痛苦、疼痛
He died very quickly,he didn’t suffer much.
他死得很快，没有多少痛苦。
2.承受，遭受
(1)You must be prepared to suffer consequences.
你要准备承担后果。
(2)He suffered defeat.
他遭受了失败。
suffer from
1.患有(疾病等)
(1)She suffers from headache.
她患头痛病。
(2)Our business has suffered from lack of investment.
我们的企业因缺乏投资而受苦。
(3)I’m suffering from a real lack of time this week.
这周我真的很缺乏时间。
(4)Mrs.White’s little boy is suffering from a bad flu bug again.
怀特太太的小男孩又患上了重感冒。