Fill in blanks with suitable prepositions or articles. Put cross (x) for zero article :

Computers are used (a)--- many ways. For example, (b)---- computer's memory may carry the names, addresses and flight numbers of air plane passengers. (c)---- ticket agent can find (d)---- almost instantly, by typing (e)---- flight number, whether there is a seat available (f)---- a particular plane. At flight time, the computer can make a list of all the passengers (g)----- the plane. Computers can also solve many problems. (h)---- many bits of information can be compared (i)---- one another. Mathematical calculations can then be performed (j)---- them.

(Fill in blanks)

We are not ungrateful to the freedom fighters.

Their contribution is the greatest thing. 

An imperative sentence expresses a command, request, advice, or suggestion. It typically starts with a base form of a verb, and the subject 'you' is often understood but not stated. To form a negative imperative, 'Do not' or 'Never' is placed at the beginning of the sentence.

In the given sentence, "You should never disrespect or forget our martyrs," 'should never' indicates a strong suggestion or advice against an action. To transform this into an imperative sentence, we remove the implied subject 'you' and the auxiliary 'should', directly starting with 'Never' to convey the strong negative command or advice.

Our government has built the national memorial with a view to paying tribute to their memories. 

 (e) A freedom fighter is greater than any other son of the soil.

Our independence was got/gotten by us for their sacrifice.