The boss gave him the push _________ (due to) his careless work.
查看答案
The __________ (combine) of the 50 states forms the United States of America.
The servants showed somewhat _________ (constrain) in the master's presence.
Can we ever ________ (elimination) poverty from the world?
It takes six years to _________ (qualify as) a doctor.
微信支付 
支付宝支付