Grep: First word in line that begins with ? and ends with?

Question

I'm trying to do a grep command that finds all lines in a file whos first word begins "as" and whos first word also ends with "ng"

How would I go about doing this using grep?

Answer 1

This should just about do it:

$ grep '^as\w*ng\b' file

Regexplanation:

^    # Matches start of the line
as   # Matches literal string as
\w   # Matches characters in word class
*    # Quantifies \w to match either zero or more
ng   # Matches literal string ng
\b   # Matches word boundary

May have missed the odd corner case.

If you only want to print the words that match and not the whole lines then use the -o option:

$ grep -o '^as\w*ng\b' file

Read man grep for all information on the available options.