Correct the given sentence gramatically.

Shreya, who she is my best friend, is a singer.

In the following question, a sentence has been given in Active/Passive voice. Out of the four alternatives suggested, select the one which best expresses the same sentence in Passive/Active voice. 
Sarla changed the curtains.

The question below consists of a set of labelled sentences. Out of the four options given, select the most logical order of the sentences to form a coherent paragraph.

By the time government
X-offices or educational institutions
Y-open, many daylight
Z-hours are already lost

The question below consists of a set of labelled sentences. Out of the four options given, select the most logical order of the sentences to form a coherent paragraph.

The room which yielded so
X-the fourth floor of a
Y-boarding-house in Bleecker Street
Z-much satisfaction to the two boys was on

In the following question, four words are given out of which one word is correctly spelt. Select the correctly spelt word.

In the following question, four words are given out of which one word is correctly spelt. Select the correctly spelt word.

In the following question, out of the four alternatives, select the alternative which is the best substitute of the words/sentence.

Not being what it purports to be

In the following question, out of the four alternatives, select the alternative which is the best substitute of the words/sentence.

Interrupt (a public speaker) with derisive or aggressive comments or abuse

In the following question, out of the four alternatives, select the alternative which will improve the bracketed part of the sentence. In case no improvement is needed, select "no improvement".
After they (had finished) eating they went for a walk.