问题描述:
Newton was playing under an apple tree___an apple fell onto his head.
A.when B.while C.after D.before
请问选择哪一个,及分别说出每个为什么对与错.
A.when B.while C.after D.before
请问选择哪一个,及分别说出每个为什么对与错.
问题解答:
我来补答展开全文阅读