Terminology

[Lily of the valley]

On my entrance exam questions concerning language will be asked, e.g. What structure is at the start of the following sentence, “On arrival and entrance to the classroom, we find the students engaged in an activity which involves animated discussion, in groups, with the teacher participating as a monitor in the activity."?

I have no idea where I can find the terms for such expressions (the Internet didn't help me). Could you please suggest some materials?

Do I understand the following exercise well?
What other words can you make from the base form of the following? assume, explanation, involves, participating

assume-assumption---I think this is the correct answer
but what can I make from the base form of explain,except for explanation?
involves-involvement
participating-participation

I have another difficulty with this exercise:
Try to find chunks or collocations in the passage, i.e. small groups of words which often appear together.
Explore the word families of these words: achievement, acquisition, characteristic.
The passage mentioned above is the following: "We might even suggest that one characteristic of the ideal second language class is one in which aptitude will not predict differences in student achievement because efficient acquisition is taking place for all students."

I don't know what I have to do with the word families of these words: achievement, acquisition, characteristic.

[5jj]

What other words can you make from the base form of the following? assume, explanation, involves, participating[/FONT]

assume-assumption---I think this is the correct answer
There are several adjectives: 'assuming', 'assumptive' (7), 'assumable' (2), and the adverb 'assumedly' (6) The bracketed numers are the number of itations in COCA, so these words are pretty uncommon.

but what can I make from the base form of explain,except for explanation?

'explanatory', 'explanatorily' (1).
involves-involvement
'involved' (adj)

participating-participation
'participate', 'participitative', 'participator' (4), 'participatory', 'participant'.

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