The following question is based on your reading of 1984 by George Orwell. Explain the Party slogan, "Who controls the past controls the future; who controls the present controls the past."

The people who had control in the past directly influenced both people who were in control and people who are living under that rule in the present, which would be the future in the past. The people in control of the present have the power to warp the past, leave it as is or supress it altogether.

the pronoun reference replaces a noun, but you have to make sure there's no room for confusion.

in the first sentence "her" could be referring to shely or to the sister. the answer there is "shelly called her sister and told her about the new baby."

in the second sentence "it" could be referring to the roof or the floor. the answer there is "since the roof leaks on the family room floor, we need to repair the roof."

the answer would be, she updates her online profiles regularly and participates in work-related online discussions.