A cloud of locust approach a field. Is this correct sentence?

The sentence "A cloud of locust approach a field" is grammatically incorrect. Here's why:

* Subject-verb agreement: The subject "cloud" is singular, but the verb "approach" is plural. They should agree in number.

* Article: The article "a" before "field" should be "the" since the field is likely a specific one already mentioned or implied.

Here are some corrected versions of the sentence:

* A cloud of locusts approaches the field.

* A cloud of locusts approaches a field. (If it's any field, not a specific one)

* A cloud of locusts are approaching the field. (This is less common, but technically correct if emphasizing the plurality of locusts)