自不量力: do sth. beyond one's ability; be unware of one's own limitation; go beyond one's depth; lack of self-knowledge; not know one's own limitation; not take a proper measure of oneself; overest
贪多嚼不烂: you bit off so big a mouthful that you were unable to chew it.; big mouthfuls often choke.; bite more than one can digest; bite off more than one can chew; have too much on one's plate; if
