In this sentence "Which of the following memories must be refreshed many times per second?" Why here we are using the Word "Refreshed" while it is present indefinite tense,,, can we not use only "Refresh"
A few days ago you asked a similar question about a sentence with a present continuous form. I explained that it had a passive infinitive. This example also has a passive infinitive.
Hello Inqilab,
A few days ago you asked a similar question about a sentence with a present continuous form. I explained that it had a passive infinitive. This example also has a passive infinitive.
must refresh = must + infinitive
must be refreshed = must + passive infinitive
Peter
The LearnEnglish Team