p______: difficult to deal with ot to understand
查看答案
f________: sth. importatnt, interesting or typical of a place or thing
c_____: an action or event that is a signal for sb. to do sth.
r________: connected in some way
c_______: have a very strong almost uncontrollable desire for (sth., esp. sth. bad)
微信支付 
支付宝支付