用法:
1 involuntary jerk of the leg when a tendon below the knee is struck 膝反射.

用法:
2 [attrib 作定语] (fig derog 比喻, 贬) done or produced automaticallyand without thought 自动的; 不经思考而做的:
a knee-jerk reaction to the mention of Communism 一提共产主义就不加思索做出的反应.

• raise to the surface(rise to the surface)
• raise(rise)
• rare(scarce)
• rarely(scarcely)
• rather than he(rather than him)
• real(really)
• referee(umpire)
• reform(reformation)
• regardless of(in spite of)
• regret doing sth(regret to do sth)
• regretful(regrettable)
• remember doing sth(remember to do sth)
• remind sb of doing sth(remind sb to do sth)
• renown(renowned)
• replace(substitute)
• represent sb as(represent sb to be)
• repute(reputation)
• request(require)
• require doing sth(require to be done)
• respectable(respectful)
• result from(result in)
• retire(retreat)
• ride(get on)
• right(rightly)
• right-hand man(right-handed man)