are you a 3d webstudent or 3d classroom student? - maybe ask your tutor when class starts on 24 august!
anyway, lets try a few things here
- press the W on keyboard - anything?
- the X on keyboard is the shortcut to hide/undie the transform gizmo you have lost!
- er ok, try going to the main menu and choose Customise > Preferences to get the Preference Settings dialog.
In this dialog make sure the Transform Gizmos ON box is checked - also make sure the Relative Sizes are 100% etc (at least over 50%)
- remeber that the - and = buttons on keyboard also make larger or smaller the transfrom gizmo, so you might have make it soooo small it is inside the objects?!....so, try pressing F3 to make objects wireframe and you might see it??
- if you are using a pirate version of max it may have the bug with no transform gizmo!