QUESTION: Fix punctuation: Interior design of a hotel for backpackers who are willing to pay a little bit extra
ANS: Interior design of a hotel for backpackers who are willing to pay a little bit extra.

QUESTION: Fix punctuation: You are looking for a beautiful evening gown because you are invited as a guest to a wedding you have no time to search the Internet for all the wellknown designers
ANS: You are looking for a beautiful evening gown, because you are invited as a guest to a wedding? you have no time, to search the Internet for all the well-known designers?

QUESTION: Fix punctuation: The Soviets decided to invade Afghanistan
ANS: The Soviets decided to invade Afghanistan.

QUESTION: Fix punctuation: I EFR heard him lecture at the University of Warwick in 1977
ANS:
I (EFR) heard him lecture at the University of Warwick in 1977.