Lack can be a verb or a noun. It means “not have.”
- If you are poor, you lack money.
- If you are busy, you lack time.
- If you are lonely, you lack friends.
To start a deep conversation, you can ask your friends:
- Is there anything you lack in life?
- What do people our age lack most?
- What does our country lack that could help it progress?
As a noun, we can use lack like this:
A lack of patience can get you in trouble.
A lack of self- control when drinking will make you sick.
FYI: The opposite of lack is the noun abundance.
A garden has an abundance of flowers.
(Of course, in casual English, you can just say “a lot of.”)