1：I'm sorry I forgot to --- (give)it back to you. 用括号的词的正确形式填空。答案give可不可以还用have given2:Look there !I--(see) you put them in the book. 答案：saw可不可以还用have seen3:Not yet.I--(look) for it everywhere,but I didn't find it. 答案looked可不可以还用look
參考答案:1。不能， I forgot to 后面必用原型，意为忘记去做某事，如要用 可用从句I forgot that i have given...
2.不能，因为前面Look there，后面只能接过去时，如果没Look there就可以
3。不能 ，but I didn't find it说明已发生，要用过去时，
