Explanation

The correct phrase is: "Although the sky was grey, we did go on our picnic."

"Did go" is the proper past tense form used for emphasis in this context.

Explanation

An Essay Concerning Human Understanding is a philosophical work written by John Locke

It first published in 1689

Explanation

Productive means پیداواری

Lucrative means منافع بخش

Explanation

In this sentence, "BUT" is a conjunction as it connects the contrasting ideas presented in the two clauses.

Explanation

The correct option is: (c) On page 3, there is an advertisement for a new video camera.

This sentence is grammatically correct and conveys the intended meaning.

It uses the preposition "for" to indicate the purpose of the advertisement, which is to promote a new video camera. 

Explanation

Adjusted: The past tense form, which correctly indicates that the schedule has been modified in the past.

Explanation

Quotidian:  عام دن

Ordinary - معمولی

Explanation

Against: This is the correct preposition.

"Leaned against" is the standard phrase used to indicate that someone is resting or supporting themselves on a vertical surface, like a wall. 

Explanation

The phrase "used to" is correctly followed by the base form of the verb to describe a habitual action in the past. 

Explanation

"The pilgrims will arrive at the Peshawar airport at 9 o'clock." 

"At" is used for specific locations and times.