Let's a song.[ ]
A. sings
B. singes
C. sing
答案:C
青春期的少男少女们都对自己的长相和体形而自卑,你会怎样开导他?
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模型底座厚薄适宜,一般腭顶和口底,的最薄处应保持()
A.30mm
B.10~20mm
C.3~5mm
D.5~10mm
E.1~2mm