A restricting factors however has been the difficulty of large scale machine manufactue beacause hand production means labour costs are high and output limited.
Нужно найти: Particliples II and I, their function
Particliples II - has been, функция - обстоятельство
Particliples I - restricting, определение
Developments however are being made in the production of block making machines which will produce vermiculite building blocks at a fairy high rate.
Найти: Predicate(tense), ing-forms, their functions
Predicate(tense) - are being, Present continuous и will produce, future simple
ing-forms - being, making, building функции - сказуемое, не знаю, определение
The densities of most vermiculite concrete blocks so far used vary from 27 lb. to 40 lb. a cu.ft. which demonstrates their lightness.
Найти: Participle II, its function, subordinate clause
Participle II - used, функция - определение
subordinate clause - which demonstrates their lightness
Two inch blocks have a 4 hour rating for the protection of structural steel.
Найти: "Rating" (participle, gerund or noun)
Это noun
Being very light in weight the blocks are easy to handle even If they are of considerable size.
Найти: Infinitive, its function, subject, participle I, its function
Infinitive - handle, функция - сказуемое
subject - blocks
participle I - Being, функция - обстоятельство
The other material with which Vermiculite has been used extensively is plaster both in the form of slabs and in-situ application.
Найти: Predicates, (tense)
Predicates - has been used, Past Perfect
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