一、–ing 作主语或宾语
1.作主语 ①直接置于句首 1) 捉弄别人是我们万万不能干的. Playing tricks on others is something we should never do. 2)学习新单词对我来说非常重要。 Learning new words is very important for me. 3)说比做容易。 Talking is easier than doing.