Celestial phenomena ranging from the auroras observed over Scandinavia to the meteor shower tracked by the Leonid monitoring station to...

Let's begin by understanding the meaning of this sentence. We'll use our understanding of pause points and segment the sentence as shown - understanding and assimilating the meaning of each segment bit by bit!

Sentence Structure

• Celestial phenomena
• ranging from the auroras observed over Scandinavia
• to the meteor shower tracked by the Leonid monitoring station
• to the comet photographed near Saturn
• [?] documented by astronomer Maria Vasquez during her three-decade career.

Understanding the Meaning

Let's start reading and understanding what this sentence is telling us:

'Celestial phenomena ranging from the auroras observed over Scandinavia
to the meteor shower tracked by the Leonid monitoring station
to the comet photographed near Saturn...'

So we're talking about:

• Different types of celestial phenomena (things happening in space)
• These include:
  • auroras over Scandinavia
  • a meteor shower tracked by the Leonid monitoring station
  • a comet photographed near Saturn

Now here's where we need to fill in the blank:

• 'Celestial phenomena... ______ documented by astronomer Maria Vasquez'

Let's look at our choices:

• A. has been (singular)
• B. were (plural)
• C. was (singular)
• D. is (singular)

We need to match the verb to our subject. What's the subject?

• 'Celestial phenomena' is our subject
• Now here's the key: 'phenomena' is already the PLURAL form
  • The singular would be 'phenomenon' (one phenomenon, many phenomena)
  • Like: one criterion, many criteria
• So we need a PLURAL verb

Looking at our choices:

• A, C, and D are all singular verbs (has, was, is go with singular subjects)
• Only B (were) is plural

So we need were - a plural verb to match 'phenomena.'

Now let's read the rest to see the complete picture:

• '...were documented by astronomer Maria Vasquez during her three-decade career.'

This tells us:

• These various celestial phenomena were all documented by the same astronomer
• This happened over the course of her thirty-year career
• 'During her three-decade career' also confirms past tense is appropriate (a completed time period)

The correct answer is B. were - it's plural (matching 'phenomena') and past tense (matching the completed time period).

GRAMMAR CONCEPT APPLIED

Matching Verbs to Their Subjects (Subject-Verb Agreement)

The verb in a sentence must match its subject in number - singular subjects take singular verbs, and plural subjects take plural verbs. This is called subject-verb agreement in grammar terms.

The challenge: Sometimes long descriptive phrases separate the subject from its verb, making it easy to lose track of what the verb needs to match.

Pattern:

• Subject (at the beginning)
• Long descriptive phrase that modifies the subject
• Verb (must still match the original subject)

In this question:

• Subject: Celestial phenomena (plural)
• Long descriptive phrase: ranging from the auroras observed over Scandinavia to the meteor shower tracked by the Leonid monitoring station to the comet photographed near Saturn
• Verb needed: were (plural, to match "phenomena")

Key insight about "phenomena":

• This word is tricky because it doesn't look plural at first glance
• "Phenomenon" = singular (one phenomenon)
• "Phenomena" = plural (many phenomena)
• Other words that work this way: criterion/criteria, datum/data

Strategy: When you see a long sentence, identify the main subject first, then skip ahead to find the verb and make sure they match - don't let the descriptive phrases in between distract you!