按照所给汉语，用英文完成下列句子
【小题1】Jack is a modest artist and never shows off，but _________________（他的作品具有说服力）.
【小题2】Working day after day last year ___________________________（使我很不开心）.
【小题3】Study hard，______________________________（否则你会落后的）.
【小题4】Be careful！You know _____________________________（失之毫厘，谬以千里）.
【小题5】—Lets' do exercise.
一_______________________________（我完全赞同）.