Clauses with there and it. Some clauses begin with the introductory words there or it rather than with the subject of the sentence. These introductory words are sometimes called expletives.
The expletive there shows that someone or something exists, usually at a particular time or place, these sentences generally follow the pattern there + verb to be + subject:
There are languages marginalised as regards the transmission of scientific results.
The expletive it is used in a number of different situations and patterns:
It is rarer for the less widely used languages to transmit scientific information, (with the verb to be + adjective + infinitive).
It takes a long time to learn a language, (with the verb to take + time phrase + infinitive).
It takes two to make a quarrel, (with the verb to take + numeral phrase + infinitive).
It is these journals that receive priority indexing in computerised files, i.e. in databases set up for the collection and circulation of scientific information., (with the verb to be + noun + relative clause).