1 (formal 正式) (used for adding a comment to what you have just said) although sth is true (用于补充刚说过的话)可是,然而:
Sales are poor this month. There may, however, be an increase before Christmas.这个月的销售量很不理想。不过,圣诞节之前也许会增长。
2 (used in questions for expressing surprise) in what way; how (用于疑问句,表示惊奇)到底以什么方式,究竟怎样:
However did you manage to find me here?你到底怎么知道我在这儿?☞ When you use only how in a question like this there is not such a feeling of surprise. 这类问句要是只用how,惊奇的语气就会减弱。
3 in whatever way 不管用什么方式或方法:
However I sat I couldn't get comfortable.我怎么坐也不舒服。You can dress however you like.你爱穿什么就穿什么。
4 (before an adjective or adverb 用于形容词或副词前) to whatever degree 不管什么程度:
He won't wear a hat however cold it is.不管天气怎么冷,他也不戴帽子。You can't catch her however fast you run.你跑得多快也追不上她。