Whatever one does ,one should do it with confidence .If one has no confidence,there is little possibility that one can achieve anything when he faces hardships,In realy ,however ,we do see a lot of people who ,always complain that they lack the ability to do something or that their difficulties are too great to overcome.For some,this might be true .But for many others,this only shows that they have lot of heart .Why do some people often feel frustrated even though they are able to do something I think there are two main reasons .In the first place ,these people don not have a correct estimate of themselves.Secondly,there is anther possibility that they exaggerate the difficulties .In my opinion ,one should build up faith in oneself as long as he has a right attitude towards his own abilities .We should neither underestimate nor overestimate our abilities.