Sentence Structure

A grammatical sentence expresses a complete thought and contains at least one subject and one finite verb that agree with each other.

• The subject is who or what the sentence is about: The audit team submitted the report.
• The predicate is everything said about the subject, built around a finite verb (one that shows tense): the team submitted the report on Friday.

A string of words with no finite verb, or no subject, is not a sentence, however long it looks. "Having reviewed the accounts in detail over three days" has no subject and no finite verb — it is a fragment.

• A phrase is a group of words that works as a unit but has no subject-plus-finite-verb pair: in the strong room, the newly appointed officer, to verify the balance, having signed the form.
• A clause does have a subject and a finite verb: the officer signed the form.

Every clause is either independent or dependent (see the next block). Being able to point to the subject and the finite verb is what tells you a clause from a phrase.

• An independent (main) clause can stand alone as a sentence: the branch reopened.
• A dependent (subordinate) clause has a subject and a verb but begins with a word that stops it standing alone — a subordinating conjunction (because, although, when, if, while, since) or a relative pronoun (who, which, that): because the branch reopened, which the auditor had flagged.

A dependent clause must attach to an independent one: Because the branch reopened, footfall rose.

• Simple: one independent clause, no dependent clause. The manager approved the transfer.
• Compound: two or more independent clauses joined by a coordinating conjunction (and, but, or, so, ...) with a comma, or by a semicolon. The manager approved the transfer, but the system rejected it.
• Complex: one independent clause plus at least one dependent clause. When the manager approved the transfer, the system rejected it.
• Compound-complex: at least two independent clauses and at least one dependent clause. When the manager approved the transfer, the system rejected it, so the clerk raised a ticket.

Count the finite verbs and the clause-starting words to classify.

1. Classify: The trainer explained the new process, and the recruits took notes while she spoke.

Finite verbs: explained, took, spoke. "The trainer explained the new process" and "the recruits took notes" are independent, joined by and with a comma. "While she spoke" is dependent. Two independent clauses plus a dependent clause makes it compound-complex.

2. Fix: Because the courier arrived late the documents missed the last dispatch.

This is not a run-on, which needs two independent clauses: "the documents missed the last dispatch" is an independent clause following an opening dependent clause, and the comma after late is missing. The clean fix is "Because the courier arrived late, the documents missed the last dispatch." A comma is needed after an opening dependent clause.

• Every sentence needs a subject and a finite verb that agree, and must express a complete thought.
• Phrase: no subject-plus-finite-verb. Clause: has both.
• Independent clause stands alone; a dependent clause starts with a subordinating conjunction or a relative pronoun and must attach to an independent clause.
• Types: simple (1 independent), compound (2+ independent, joined by a comma and a coordinating conjunction or a semicolon), complex (1 independent + 1+ dependent), compound-complex (2+ independent + 1+ dependent).
• Fragment: no main clause. Run-on: two independent clauses with nothing between. Comma splice: two independent clauses joined by only a comma. Fix with a full stop, a semicolon, or a comma plus a coordinating conjunction — or subordinate one clause.
• Put a comma after an opening dependent clause.

Classify each as simple, compound, complex or compound-complex; then repair items 5 and 6.

1. The regional office issued a circular about the revised charges.
2. The clerk verified the signature, and the cashier counted the notes.
3. Since the network was down, the branch processed withdrawals manually.
4. After the auditor left, the team finalised the report, and the manager signed it that evening.
5. Whenever the quarterly targets are announced. (repair)
6. The queue was long the counter staff were slow. (repair)
7. The auditor reviewed the file, but she found no error, so she signed off.
8. To meet the deadline. (repair)