Only when______ can the postal code system achieve its full efficiency.
A. all the post offices in the country have the fight machines
B. all the post offices have trained staff
C. most post offices have the right machines
D. most post offices have trained staff
A mother will affect her unborn baby if______.
A. she is emotionally shocked
B. she has a good knowledge of inheritance
C. she takes part in all kinds of activities
D. she sticks to studying
Which of the following is an appropriate title for the passage？______.
A. Role of Inheritance
B. An Unborn Child
C. Function of Instincts
D. Poetry and Music
微信支付 
支付宝支付