单项选择题
The ambiguity of the sentence, 'John ran the egg and spoon race', is due to ().
判断题 中国的半殖民地半封建社会以1840年的鸦片为起点，以1911年辛亥革命建立中华民国为终点。
单项选择题 ( ) dictionaries aim at defining words and explaining their usages in the language.
单项选择题 'teacher and 'student are ( ).
