Read the sentences and express your advice using modal verb should + Perfect Infinitive.
1. My friend caught a cold but he didn't go to the doctor.
2. He couldn't work with his computer because something got wrong with it.But he didn't ask anybody for help.
3.He couldn't use the computer programme because he didn't have CD-ROM in his computer.
4. She couldn't send me an electronic letter because she didn't know my E-mail.