Most exclamations in English are preceded by what or how:

–What terrible weather!
–How awful!

What is used much more frequently than how in everyday language.

Exclamations can be as brief as one or two words (What a mess!) or as long as a sentence:

–What a way to end my vacation!

NOTE: Don't forget that what and how are most frequently used in questions:

–What did you say?
–How much does it cost?

Examples of Exclamations

• Look, there's an inch of water on the floor. What a mess! Can you fix it?
• How could I? I've been out of town for weeks. What a way to end my trip!