由于温度变化引起的零件变形称（）。
参考答案：热变形
—What beautiful shoes you're wearing! They must be ex.pensive.
—No. they only ______ 10 yuan.[ ]
A. spent
B. took
C. paid
D. cost
瘢痕性幽门梗阻最主要的临床表现是
A．呕吐大量隔餐或隔夜食物
B．消瘦
C．上腹胀痛
D．胃型及胃蠕动波
E．食欲减退
