1.当然可以用英语是:Certainly,[英][ˈsɜ:tnli][美][ˈsɜ:rtnli]。
2.你当然可以通过直接向他们捐款来帮助他们。You can of course help by giving them a donation directly。
3.你当然可以想方设法摆脱,但最后你会发现自己还是像以前一样拼命抽烟。You can simply go on putting off the evil day and eventually find yourself smoking as much as ever。