Fill in the blanks with simple past and past perfect tense form of the verbs given in brackets.
When the delegates ____ (arrive) at the conference, the keynote speaker ____ (already begin) the session.
arrived, had already begun
After the students ____ (learn) how to identify fake news online, they ____ (start) verifying information before sharing it.
had learned, started
Before Kiran ____ (start) using digital payment platforms, she ____ (ensure) her understanding of online fraud prevention.
started, had ensured
By the time Varun ____ (recognise) the importance of budgeting, he ____ (exhaust) most of his savings.
recognised, had exhausted
When Raghu ____ (log in) to the cybersecurity webinar, the instructor ____ (already discuss) the importance of strong passwords.
logged in, had already discussed
Explanation
The textbook states that we use the past perfect tense to indicate two completed actions, where the more recent action is expressed in the simple past tense, and the earlier action takes the past perfect tense. In (A), the speaker beginning the session occurred earlier (had already begun), and the delegates arriving is the more recent action (arrived). In (B), learning happened first (had learned), followed by starting (started). In (C), ensuring understanding was the earlier action (had ensured), and starting to use platforms is more recent (started). In (D), exhausting savings happened earlier (had exhausted), and recognising the importance is more recent (recognised). In (E), the instructor discussing occurred earlier (had already discussed), and Raghu logging in is the more recent action (logged in).