In my opinion,it is possible for you to find some real good friends with the help of new technology but you (28) ______ ______ take care.When you talk with someone unknown on the Internet,you have no idea at all what kind of person he is and (29) ______ he is telling you the truth.
28.have to/ ought to 29.whether/ if
帮我分析一下他的语法谢谢!