greatly over-rate [overestimate] oneself; think too much [highly] of oneself; too bold and over-confident
Related Translations:
不自量: not take a proper measure of oneself; overrate one's own abilities; do sth. beyond one's ability or strength; overconfident; be unaware of one's own limitations [impotence; weaknesses]; go
可笑不自量: cut a ridiculous figure because of self-overestimation; make a laughing-stock of oneself by overrating oneself; make oneself ridiculous by overestimating one's ability; ridiculously overra
蚍蜉撼大树可笑不自量: a tiny insect trying to shake a mighty tree is ludicrously ignorant of its own weakness