4 a) Read the signs below. Now tell a friend what you must, mustn't or can't do when you are in the library, as in the example.

Library Rules - Exercise 4a

Here's what you must, mustn't, or can't do in the New Glasgow Public Library, based on the signs:

• You mustn't talk when you are in the reading room. (From the "NO TALKING IN THE READING ROOM" sign)
• You mustn't use your mobile phone. (From the "Turn off mobile phone" sign)
• You mustn't eat or drink in the library. (From the "No food or drinks in the library" sign)
• You mustn't smoke. (From the "Smoking is prohibited" sign)
• You must show your card to the librarian when taking out books. (From the "Show your card to the librarian when taking out books" sign)

Explanation: The sentences are formed using 'must' for rules and 'mustn't' for prohibitions, directly derived from the provided signs.