Help the busy office worker finish her quick text message to a friend by choosing the correct word for each gap.

I cannot meet you for lunch because I do not have any free time today! My boss has a very important meeting at noon, and I need to help him prepare. Plus, three new clients are having coffee in the waiting room right now, and they look impatient!

I cannot meet you for lunch because I do not have any free time today!

After the negative auxiliary "do not" (or "don't"), we always use the base form of the verb, which is "have".

My boss has a very important meeting at noon, and I need to help him prepare.

"My boss" is a third-person singular subject (he/she), so we use "has" to talk about his scheduled activities.

Plus, three new clients are having coffee in the waiting room right now, and they look impatient!

For an action happening at this exact moment (drinking coffee), we use the present continuous form ("are having").