I just want to ask something about the usage of sentences. How can we know when we are going to use “to be -ed” or “to be -ing”?
I give the examples extracted from the newspaper as following:
- “We are concerned over this issue as the list seems to be expanding from drinks to foods”
- “Samples have been taken to be analysed”
Up. Could somebody here please help me to figure out my problem?
I think, using “to be -ing” as in you example (as the list seems to be expanding from drinks to foods)
is an active voice, meaning, the list is expanding from drinks to food, so the list is the subject.
As for “to be -ed” as in you example “Samples have been taken to be analysed” it is a passive voice, meaning, someone will analyze the samples, so the samples are the object.
In the passive voice there is only the verb and the object, no subject to be mentiond. And in the active we mention the verb and the subject
you can find more information by studing the passive voice
Hope that will help you a little
Many thanks to you, Farisiam. I think, I get a better understanding right now.