We saw the sun ________ behind clouds and then it began to rain heavily. (appear)
题目考点:动词ing形式;see+宾语+现在分词
答案:
appearing
解析:
句子为“We saw the sun ______ behind clouds and then it began to rain heavily.” 动词see后可以接“宾语 + 现在分词/不定式”,表示看到某事正在发生。 此处要用appear的现在分词形式appearing,表示“我们看到太阳出现在云后”。