and/or

Most authorities recommend avoiding the expression and/or.

When used with only two options, and/or means that the possible choices include either one or the other of the two options, or both of them together (either A or B, or both).

• On Saturday, we can go to dinner and/or to a play.
  [We can go to dinner or to a play, or both.]

However, and/or is unclear when used with three or more options. In addition, its use in legal writing has created serious problems in interpretation. Many also find it unattractive. For these reasons, we recommend that you avoid it by using one of the methods below.

Most situations can be expressed using and or or separately.

• The volleyball team is made up of women and men.
• The French language courses will be held in Ottawa or Hull.

When both meanings are necessary, write or between the two choices, followed by the phrase or both.

• Would you like to go hiking or biking, or both?