As sick as a dog

Meaning:

If we are as sick as a dog, we are very sick. We often use this one if the person has a stomach sickness and is vomiting. We can also use it if someone has a bad cold or flu.

Example sentences:

1. I'm as sick as a dog.
2. She was as sick as a dog last night.
3. He cannot go to work because he's as sick as a dog.

Example dialogue:

A man is talking to his coworker about why he did not go to a meeting at work.

A: Hey, Bob. I didn't see you at the meeting yesterday. What happened to you?
B: I couldn't make it because I came down with the flu.
A: Oh, really? That's too bad. Was it serious?
B: Well, it was only a 24-hour flu, but for those 24 hours, I was as sick as a dog.

Practice:

When was the last time you were as sick as a dog?