解题思路： 1.在现在进行时中要用-ing形式。2.在一些动词或动词短语后面常跟动词-ing作宾语。
解题过程：
加-ing形式大致有两种情况：
1.在现在进行时中要用-ing形式。
现在进行时由be动词(am/is/are)+动词的-ing形式构成。此时的-ing形式叫作动词的现在分词。
如：
He is studying.他正在学习。
l am doing my homework now.我正在做功课
2.在一些动词或动词短语后面常跟动词-ing作宾语，此时的-ing形式叫作动名词，这类动词目前学过的有like , enjoy, finish, keep, mind, miss, practice，look forward to,think of 等。如：
He practices speaking English every day.
She likes doing housework.
He enjoys playing the computer.
Have you finish reading the book?
They are looking forward to seeing her . We are thinking of going to France.
最终答案：略
