几个英语单词的辨析请教whereas,otherwise,however,nonetheless,nevertheles

whereas,however,连词,在连接两个句子时候完全等于but,就是比较书面用语,常用度however>whereas.
otherwise 否则,连词.和汉语否则一样用.
nontheless完全等于nevertheless,比前两个多个副词功能.可以当副词拿出来用.