Rachel · September 22, 2026 · Class 03
Class Summary
Today we worked through section 1 of Sentence Core & Verb Roles and section 1 of Sentence Boundaries · Remaining Practice. Use the complete sentence structure to explain each verb form and punctuation choice.
1. Find each clause and its predicate
- A finite verb group carries tense or a modal. Identify the whole group: records · was collected · has changed · may change. A sentence can contain more than one clause, each with its own predicate.
The report that compares readings from two stations challenges the assumption that the entire valley has the same climate.
- Main core: The report challenges the assumption. Compares belongs to the relative clause describing the report; has belongs to the clause giving the assumption’s content.
Although the evidence was limited, the researchers reached a conclusion.
- The although-clause has a finite verb, but it depends on the main clause to complete this statement.
2. Separate a predicate from a nonfinite modifier
The team is analysing the samples.
The team analysing the samples works upstairs.
The team analysing the samples works upstairs.
- In the first sentence, is analysing is the finite predicate. In the second, analysing the samples describes the team; works is the predicate. An -ing form alone does not automatically make a present-progressive verb.
The technicians inspecting the sensor right now have found a loose connection.
- Right now belongs inside the description. The sentence still needs the finite predicate have found. Decide from the blank’s role, not a time expression alone.
3. Decide who performs or receives the action
The researchers collecting the samples work upstairs.
The samples collected by the researchers remain in storage.
The samples collected by the researchers remain in storage.
- Researchers perform the collecting: collecting. Samples receive the action: collected. The second collected is a passive participial modifier; it is not the sentence’s past-tense predicate.
The technicians collected the samples yesterday.
The technicians have collected the samples.
The samples were collected yesterday.
The technicians have collected the samples.
The samples were collected yesterday.
- These are past simple, present perfect, and past passive respectively. Regular verbs can use the same -ed spelling for different jobs. A thing can also receive an action: The report reviewed by two editors is ready.
4. Keep the true subject and necessary complements
The collection of letters that the archivists recovered reveals how the settlement expanded.
- The head of the main subject is singular collection, so use reveals. The relative clause describes the letters; its verb recovered does not control the main verb.
The samples (that) the technicians collected during the survey reveal a change.
- That can be omitted in this object-relative clause. Collected remains finite because its subject is the technicians. Removing that does not automatically turn a verb into a participle.
The samples were stored in a refrigerated cabinet.
The next sample to analyse is on the tray.
The next sample to analyse is on the tray.
- Cabinet is the object of the preposition in, not the direct object of were stored. Keep a necessary complement when stating a complete core: The sample is on the tray, not “The sample is.”
5. Use infinitives for their role
To compare the samples, the team uses one scale.
The next sample to analyse is on the tray.
The next sample to analyse is on the tray.
- To compare gives a purpose; to analyse describes the sample. An infinitive may refer to an intended action, but it is not automatically a future tense. To understand this result is difficult makes a present statement.
6. Do not split a subject from its predicate
The results from both stations suggest a change.
- Do not insert a comma simply because the subject is long. Find its head and its predicate first. Likewise, keep a verb connected to its object: The researchers analysed the samples.
The results, which were checked twice, suggest a change.
- Here the two commas enclose a supplement. Remove the entire supplement and both commas: The results suggest a change. The closing comma before suggest has a valid job.
After collecting the samples, the researchers returned to the laboratory.
The samples remained sealed, protecting their contents from contamination.
The samples remained sealed, protecting their contents from contamination.
- A nonfinite phrase cannot stand alone as a complete sentence. Check whether it introduces or supplements the main clause before choosing its boundary.
7. Keep tense, aspect and voice separate
I ate lunch at noon.
I have eaten lunch, so I am not hungry.
I have lived here for three years.
I have eaten lunch, so I am not hungry.
I have lived here for three years.
- Present perfect can describe a completed event with present relevance or a situation continuing to the present. No written date does not automatically mean present perfect. Tense and active/passive voice answer different questions.
HM
Complete 20 questions: 10 grammar and 10 punctuation. The grammar set includes seven questions testing finite and nonfinite verb forms, including active/passive participles and purpose infinitives.
For each question, mark the relevant subject and predicate in your working. Add a short reason for your choice, especially when you are unsure. Check the sentence structure before submitting.