【单选题】Enclosed are sample parts ____ some of the problems we encountered.
【单选题】We encountered the pathetic sight of a family packing up its home..
【单选题】We have encountered ________ problems.
【单选题】We have encountered _____ problems.
【单选题】The polarity of U2 encountered first as we travel around the loop is ( ).
【单选题】We encountered a number of difficulties in the initial stages of the project.
【简答题】We are forced to invent new operations as we encountered ________( 先天的 ) abnormalities in newborns.