Modals of Probability and Possibility

Question

A: Rita's sneezing again.

B: Yes, she _________ a terrible cold.

(must have / must be having / must have had)

My answer for this is: Yes, she "must have" a terrible cold.

In my opinion, "must be having" shouldn't be used here because "having" in this sentence is a stative verb/non-action verb and it has no continuous (progressive) form.

On the other hand, "must have had" is in Present Perfect Tense and can't be used here because it'll imply that the action begun in the past that has already been completed.

The thing that makes me confused is the adverb "again." I hope someone can help me with my sentence. Thanks a lot!

Answer 1

Generally speaking, one has a cold. If you use must, it becomes: she must have a cold. To have a cold is a verb phrase with an adjective. It is also an idiom.

Must can be followed by be + an active verb or must be or have plus an adjective or noun.

• must be + active verb ing: must be going, must be seeing. etc.
• must be [rich, nice, awful, etc.] or must have [a house, a cold, coffee, etc.].

One could, of course, find utterances such as: She must be having a good time. where to have a good time is an idiomatic expression and may be used with an active verb.

The use of again does not change the fact of using the simple present tense here since to have a cold in the present is never used with an active verb.

If the sentence with again were different, the verb could be an active one:

• Rita's laughing again. She must be having a good time. [to have a good time].

The use of must I have explained does not include the use of the modal to express a duty or obligation.

Answer 2

Again means this is the second time something is happening or starting.

If she's sneezing again, her cold is not "completed", so there is no "previous cold". Thus you can't say must have had. Use must have or must be having.