Questions

The primary purpose of an operating system is to make the most efficient use of the computer hardware.

Rabindranath Tagore called Subhash Chandra Bose as Desh Nayak for the first time.

Tatra not an Air Defence Missile System. It is a Czech manufacturer producing vehicles in Koprivnice. It is owned by the Tatra Trucks company, based in Ostrava, and is the third oldest company in the world producing cars with an unbroken history.

If some action has started in the past and is still continuing, then present perfect continuous tense should be used instead of present continuous tense. So, the phrase ‘am waiting’ needs to be replaced with ‘have been waiting’ to make the sentence contextually correct. Thus, the correct formation would be, ‘I have been waiting for three –quarters of an hour’.

‘Regret for’ needs to be replaced with ‘regret’ to make the sentence grammatically correct. This is because ‘regret’ is not followed by a preposition. Thus, the correct formation would be, ‘I regret using objectionable words against a man so mighty’.