单句改错，下列句子均有一处错误，请指出并改正。

1. Is(A) these(B) your(C) photos(D)?                                

2. What's(A) those(B) in(C) Chinese(D)?                           

3. Nice(A) to(B) meet(C) your(D).                                    

4. Those(A) aren't(B) her(C) watchs(D).                            

5. Do(A) you(B) his(C) friend(D)?                                      

尺寸角度要求较高的铣刀应选择（）后角。